Suspension set-up

As promised, here is the long awaited round up of our suspension system. I know some of you have been itching to find out how we’ve managed to get the car to corner so well (despite the handicap of swing axles, crossply tyres and an almost stock ride height) So here it is in a nutshell:

Front Suspension

Balljoint beam with stock leaves, stock rubber bushes and a pair of Sway-A-Way adjusters
1 set of caster shims
2.5” drop spindles
Camber adjusters (2 degrees negative camber)
Tracking 5mm (3/16”) Toe-in
Formula Vee ‘adjustable’ anti-roll bar
Custom made Quantum ‘double adjustable’ dampers
Ride height: 2” lower than stock (note: front is set 1” higher than rear)
Wheels: 5x15” JGE Raders
Front tyres: Dunlop L500 treaded crossply historic racing tyres (120mm tread width)
Front tyre pressures: 22psi cold (25psi hot)

Rear Suspension

Stock ‘soft’ torsion bars and stock rubber grommets
Lowered to acheive the optimum camber (3.5 degrees negative camber)
Tracking 2mm (1/16”) Toe-in
Custom made heavy duty ‘adjustable’ Z-bar
Custom made Quantum ‘double adjustable’ dampers
Ride height: 3” lower than stock (note: rear is set 1” lower than front)
Wheels: 5x15” JGE Raders with 10mm wheel spacers to widen the track by 20mm
Rear tyres: Dunlop L550 treaded crossply historic racing tyres (135mm tread width)
Rear tyre pressures: 25psi cold (28psi hot)

One interesting thing to note is that our suspension set-up goes against all current thinking in Beetle racing, and has more in common with a formula Vee than an old Beetle Cup car (Formula Vees are single seater racing cars that use Beetle suspension, brakes, gearbox and engine. First raced in the 1960’s, these cars are now ‘state of the art’ bits of kit, capable of lap times similar to a modern BTCC Touring Car)...Here are some comparisons between ours and a typical Beetle Cup set-up:

See what i mean?....It’s like we’ve done the complete opposite ‘on purpose!’

There will be many ‘experts’ out there telling you that “we’ve done it all wrong!”....”The ride height is ‘too high”, “the springs are ‘too soft”, “we should use toe-out, ‘not toe-in’ on the front”, “the tyres are ‘too tall’ and ‘too skinny”, “we should use urethane bushes” etc. But then these are the same people that turn up at the Drags with a 2387cc engine with the largest cam and carbs and then get beaten by a bloke with a 1776!....The 1776 probably had a better ‘combination’ of parts. Not the wildest cam or largest carbs, but a selection of parts ‘that have been proven to work’.

It’s much the same with suspension, It’s not about having the lowest car with the stiffest springs and widest tyres....you’ve got to be cleverer than that! The ride height, springs, dampers, tyres, front and rear bars, front and rear cambers, caster, toe angles and tyre pressures of our car have been carefully chosen to ‘work with each other’ in order to get the most out of the car. A low centre of gravity IS very important, but it’s not the be all and end all. The Beetle chassis is a unique design and what works on a Honda Civic isn’t always going to work on a Beetle.

I remember Julian Lock (in the early days of the BeetleCup, when he was virtually unbeatable) saying “everyones lowering their front ends too much...when you lower the front too much, it screws up the steering and suspension geometry”.....and that’s always stuck in my mind.

I’ll try and explain our set-up in a bit more detail so that you can understand the reasons why we’ve picked a set-up that ‘works on-track’ but makes no sense ‘on-paper’....I’ll try and pre-empt your questions!

Q: Why would you go to the trouble of fitting axle adjusters AND drop spindles?
A: The disadvantage of drop spindles is A ‘the cost’ and B ‘the added unsprung weight’, but they make up for this by lowering the car ‘and more importantly’ keep the suspension arms at the factory angle (i.e pointing downwards) so that the suspension and steering work as they were designed to. The Sway-A-Ways are purely there to allow us to fine tune the ride height.

Q: Why have you chosen front Toe-in when Toe-out is better?
A: Toe-out IS known to be better for cornering grip, but it can also unsettle the car under braking, especially on wet or undulating surfaces. Imagine if you have to fight the car entering a corner....your mind is going to be on controlling the car, not on speed. We already have good front end grip, so Toe-in allows me to concentrate fully on getting the best exit...and it’s the exit speed that counts! All of our settings mentioned above are designed to make the car as easy to drive as possible.

Q: Why have you only lowered the car a couple of inches? the centre of gravity will be too high!
A: The historic crossply tyres that we have to use, work best with softer springs. If we lower the car any more, the car will bottom out or hit the bump stops, neither of which you want at racing speeds. Softer springs also offer better tyre grip than hard springs and allow us to ‘monster’ the kerbs without unsettling the car (see pic below). We’ve lowered the centre of gravity significantly by relocating items to the floor of the car, fitted a steering column that is 6kg lighter, adding polycarbonate side and rear windows etc. The car now only weighs 685kg (soon to be 635kg) so body roll is minimal, despite the soft springs. The reason why the car is 1 inch higher at the front than the rear is because it improves straight line and cornering stability. (you’ll see this time and time again if you look at rear engined cars throughout history. It’s all to do with aerodynamics and the polar axis of a rear engined car)

Q: Why go for such skinny tyres? 125mm and 135mm!!
A: There are only a limited number of tyre sizes to choose from. Dunlop crossplys have narrower treads than modern radials and these are the widest tyres that we can fit under the wheel arches. We may experiment with wider tyres at a later date, but wider tyres ‘may’ not give us any more grip as the car is so light that the tyres may not be able to get up to the optimum temperature. Have you seen the front tyres on a Vauxhall VX220? They have very skinny tyres ‘presumably’ for the same reason (135 or 145mm) and they are known to be one of the best handling cars out there.

Q: Why go to the trouble (and expense) of having dampers custom made?
A: The Quantum dampers were expensive, but they have been built ‘to order’ to match the precise characteristics of our car, and having driven it, it’s proved to be money well spent, especially when you consider that they are rebuildable and should last the life of the car. They also offer adjustable bump and rebound and this is one of the key features of the car ‘adjustability’. This is why we have an adjustable anti-roll bar and Z-bar. Next season we will start to experiment with various combinations of bar settings, damper settings and tyre pressures to tweek the handling further. GAC that built the suspension are confident that we can find another 1 or 2 seconds, just from fine-tuning our current set-up. (race pics below Courtesy of www.mattsayle.co.uk)

When driving a car ‘on the limit’ the driver has to ‘manage’ the weight transfer, so that each tyre is doing its fare share. This means not overdriving the car and overtaxing the tyres. If you watch in-car movies of top drivers, they may turn the steering wheel fast and brake hard, but there are no jerky movements, everything is a smooth flow. The secret to our Beetles handling is that these dampers (combined with the soft springs and plenty of suspension travel) soften the weight transfer allowing the car to turn fast into corners without overtaxing the tyres.

When you corner hard, weight transfers to the outside tyres. If there is too much weight transfer or it happens too quickly the grip will suffer. Contrary to popular belief, there is nothing you can do with springs, dampers or anti-roll bars to reduce the amount of weight transfer, the only way that you can reduce the total weight transfer is to make the car wider or lower the centre of gravity. Apart from lowering the suspension, all that springs, dampers or anti-roll bars can do is ‘slow’ the weight transfer down. Our dampers act much like hydraulic rams, slowing this process down. Once turned into the corner, the car ‘gradually’ squats down and plants the tyres without overburdening them.

In the diagram below we have 2 Beetles, both are identical apart from the suspension settings. Beetle ‘A’ is heavily lowered with stiff springs and very little suspension travel, Beetle ‘B’ is our car with mild lowering, soft springs, plenty of suspension travel plus our Quantum dampers. For the purpose of this exercise, both cars weigh 800kg (400kg on the left and 400kg on the right) When car ‘A’ turns into the corner it’s low centre of gravity means that it transfers an extra 100kg to the outside tyres and loses 100kg from the inside tyres, this is quite normal and not a problem. When car ‘B’ turns into the same corner it transfers 120kg to the outside tyres (20kg more than car ‘A’) This is the higher centre of gravity working against it.

Car ‘A’ actually has an advantage because of this, but due to it’s limited suspension travel and stiff setup, car ‘A’ transfers this extra 100kg to the outside tyres ‘instantly’ as soon as the car turns into the corner. The driver of this car needs to keep his wits about him as this car could very quickly break traction or swap ends at that turning-in point. Car ‘B’ on the other hand takes nearly a second (or 100 feet at 70mph) to transfer the extra 100kg, so the tyres are better able to cope with the transition, it also keeps more of the cars weight on the inside tyres than car ‘A’ so the weight of the car is being spread more evenly over the four tyres for more of the time.

After a full second car ‘B’ shifts an additional 20kg to the outside tyres (higher centre of gravity remember) but it is more able to cope with this extra 20% as again its a slow transition. In addition to this, if both of these cars were to get into a slide, car ‘A’ will be much harder to control because there will be very little warning of an impending spin and the spin will happen very quickly. Car ‘B’ will react much slower, giving the driver more time to catch the spin and the car will be more forgiving, it will also be much easier to drive in the wet as softer set-ups provide better grip on wet surfaces.

So there you have it...A Beetle that can match a race prepped Mini Cooper S in the bends...who’d have thought it! But before you get carried away and use these suspension settings on your own car, bare in mind that this is a car that uses tyre technology from the 1950’s. The lack of body roll may also be, in part down to the fact these these tyres don’t generate enough grip. If we were to put modern grippy tyres on the car the weight transfer would increase and possibly unsettle the car enough to require us to run a fraction lower and stiffer.

This isn’t meant to be the definitive suspension set-up for your Beetle that will guarantee you trips to the podium. A cars suspension set-up relies on so many variables, such as the cars weight, weight distribution, centre of gravity, the cars relative speed to others, wheel size, tyre size, tyre type, driving style etc. If any one of these factors on your Beetle are different from ours, your set-up WILL be different....The best set-up for your car may be the complete opposite of ours, more like a BeetleCup or BeetleChallenge car (low and stiff). Maximising a cars handling is a bit of a black art, even the best teams in the world get it wrong (how many times do you hear Formula one drivers moaning about the cars set-up?)

If you want your car to handle well on road or racetrack (something similar to ours would be the better option for the street) speak to as many people as possible, go on the web, go and see the guys that race in the BeetleChallenge (the successor the the BeetleCup) They are a great bunch and they’ll be more than happy to spill their secrets like us. Visit www.beetlechallenge.com

Once you’ve gathered enough info, it’s up to you to choose a set-up that works for you, then make the necessary adjustments to get it right. Don’t be tempted to make adjustments straight away though...get used to the feel of the car first. It may surprise you to know that we haven’t touched the suspension yet...they are still the same settings that the car had when it was built! But now that i’ve spent 4 races in the car, I’ll be better able to ‘feel’ any improvements that come from making any changes to the car.

I hope we’ve proved a point..that there’s more to life than an EMPI anti-roll bar and a set of Koni’s! Go out there and try stuff out. If it works...tell everyone about it, then we can all go faster!

If after reading this you’re still not convinced that our set-up works, take a look at our onboard movies on youtube. Our straight line speed was poor (4th gear was too tall!) but it was able to make back some of that time lost in the bends. (more speed coming next year)

Highlights Movie:
http://www.youtube.com/watch?v=rARRdwc-tU4

Oulton Park (part 1):
http://www.youtube.com/watch?v=fZ949l650M0

Oulton Park (part 2):
http://www.youtube.com/watch?v=3TEkaJl_7M8

Mallory Park:
http://www.youtube.com/watch?v=IVbqyMg-4e8


In the next blog I will do a round up of our first season and share with you what we’ve learned.

Bye for now!

Ian

Brands Hatch

I’d been looking forward to Brands Hatch for some time as this was where the Beetle first turned its wheels in anger. It was also the scene of my first ever circuit race back in July which ended with the car and me coming away with a trophy and our first class win.

Based on the cars performance at previous tracks, Brands looked like being my best shot at a good result as i’d driven the circuit before and being the short ‘Indy’ circuit this time, it was nearly all 3rd gear which suited the engine better.

With this in mind, it was the most relaxing start to a race weekend that i’d had. The car sailed through scrutineering as usual, but I was caught out when we were called up to the collection area for qualifying far earlier than normal and forgot to double check the tyre pressures, something I always do just before going on track. The reason for the early call turned out to be the sound test for everyone. The cars mustn’t exceed 105dB at 3/4 of the maximum revs (for us that’s 6000rpm) Once we’d all been tested, we went out on track for the 15 minute qualifying session.

After a couple of warm up laps (to warm the engine, gearbox, brakes and tyres) I pushed a little harder but found the car to be quite slidy. I had understeer through Graham Hill Bend and massive oversteer through Surtees, which I put down to the track being greasy from an earlier light shower. What I didn’t realise at the time was that my tyre pressures were too low (Racing tyres lose air quicker than road tyres and need constant topping up) This was having a detrimental effect on the handling.

After lap 4 the tyres had warmed fully which helped raise the tyre pressures somewhat and the car felt a bit more grippy, but I still couldn’t push it as hard as i’d like and I was having trouble settling into a good lap, which was made harder by the fact that the ‘Indy’ circuit is only 1.2 miles long and with 22 cars on it, you always seemed to have someone in your way or a faster car right up your backside. The result after 11 laps was a 1:05.1 (2 seconds slower than I was expecting) which put me 18th out of 22 cars and 3rd in my class. Behind me was a Hillman Imp, Triumph 2000 mk1, Alfa Romeo Guilia Sprint GT and a Mini Cooper S. If I was going to get some decent points at Brands, I was going to have to do a stella drive in the race.

I’d been having problems with the new starter motor all weekend which meant bump starting the car occasionally. The starter motor is fine, but the cars been suffering from electrical gremlins since the last round at Oulton Park and this was possibly linked to it. I nearly missed qualifying altogether because the starter wouldn’t turn! I didn’t want this to happen just before the race, so when the race came I left the engine running in the collection area, this unfortunately fouled the plugs (this is what happens when you put a pair of 44 Webers on a 1300!) When I went out on the warm up lap, the car ran like a dog! (I had the same problem when I tried Drag Racing it at BugJam earlier in the year) It sometimes takes a few miles to clear.

When the race started the car misfired horribly off the line and wouldn’t pull at all, so I got swamped by everybody and went round the first bend ‘Paddock’ dead last. I caught up with the pack as they bunched up at the ‘Druids’ hairpin and managed to re-pass the Alfa Sprint GT down the hill and through ‘Graham Hill Bend’. Along the ‘Cooper Straight’ the Alfa took the lead again as the Beetle refused to rev any higher than 6000rpm. Then while turning through ‘Surtees’ and ‘Clark Curve’ the sparkplugs cleared themselves and the engine roared into life...horay! “Now I can set about making back those lost places” I thought. The engines doing 8100rpm in 3rd (82mph) out of ‘Clark Curve’ and I’m just about to shift into 4th. At this point there is a big vibration and a huge bang and the engine cuts out!

I pull onto the grass and the first thing that springs to mind is ‘The engines just thrown a rod’. As I get out of the car the red flags come out and the race is stopped. The marshalls said that there is oil all over the circuit and asked if it was me. I had a look under the car and all was well. It turned out to be one of the other Alfas that had an engine let go on the same lap. I opened the engine lid to find a huge hole in the top of the fan shroud and I knew straight away what it was. The new balanced and welded ‘race fan’ had exploded, shredding the fan shroud, snapping the alternator stand in half and more importantly destroyed the fins on the offside barrels and the ‘very expensive’ cylinder head. Annoying as the fan was only 4 races old and we were only a couple of races from replacing it with an electric version and doubly annoying in that the Mini ahead of us failed to finish which would have given us enough points to end the Championship season 2nd in the 1151 to 1300cc class. Still 3rd in a class which is all Mini Coopers isn’t too bad for our first season, especially as we’d missed the first 5 rounds.

The final round is at Silverstone on October 17th, but we won’t be there as the engine needs stripping down and I’m at a wedding that weekend. So that’s our first years racing over. Now we can start to put everything that we have learned into improving the car for next season. Plans over the winter are less weight, more power, suspension adjustments, a lower 4th gear and possibly a torque-bias differential, and of course an electric cooling fan conversion.

Even changing one of these items will make a huge difference to the cars lap times, so next years looking very exiting. The aim is to be somewhere in the mid-pack by the end of 2010, then after that, who knows!

Now...the racing may be over, but the blog goes on....Over the Winter break, I will cover all the improvements that we have made to the car and then we’ll take the Beetle testing to see if progress has been made.

In the next blog I will complete the feature (promised months ago!) on our suspension set-up, which worked so well...proof that a swing axle Beetle with mild lowering can go round corners!

See you then

Ian

Oulton Park (Gold Cup) Race.

I was looking forward to Oulton Park. It’s one of the countries best tracks and we were entered in two races. firstly a 20 minute HSCC points race and later in the day a one hour, two driver race for pre-1966 Touring Cars.

First job was to learn the circuit, so we had two 20 minute test sessions on Saturday morning. One for me to learn the 2.7 mile Oulton Park International circuit and one for Jeff the second driver who already knows the track, but doesn’t know the car. The weather was unpredictable all weekend, so mine was dry and jeffs was wet.

It’s a great circuit and it was clear that it suited the Beetle much better than Mallory Park. Lack of time meant that the car was unchanged from the last round, so we were still lumbered with a 4th gear that was too tall, meaning no acceleration on the faster parts of the track, which was firstly ruining our lap times and secondly making it hard for us to defend ourselves on the straights during the race. Compounding the problem was that we were still 55kg overweight (despite losing 10kg myself!!) and ran out of time to squeeze the extra 10-15bhp from the motor.



Still....Things were looking good. We weren’t far off the pace and what we were losing on the straights, we were making back under braking and through the corners.

Firstly my qualifying for the 20 minute race was dry. I went out behind a Mini Cooper which I could match on power but in the corners it kept slowing me down. I put up with it for a lap, then pulled back to make some space. With a clear lap I out-qualifed the Mini by 1.5 seconds. My best time was a 2:24 which put me 4th in class and 19th out of 23 cars. ahead of an Austin A40, Alfa Romeo Guilia Sprint GT and two Mini Coopers. The Mini mentioned earlier, didn’t make the grid so it’s place was taken up by a 4.7 litre Ford Mustang (I managed to keep the Mustang behind me for 2 corners!!)

In the race I passed a Hillman Imp and another Alfa Sprint off the start, but at the same time lost positions to the remaining Mini behind me and the Mustang. On the first lap the Tacho started playing up, meaning that the needle was going all over the place, then as the race went on it was clear that I had some electrical fault which was cutting the ignition, sometimes for a split second and other times for more than 5 seconds, which enabled the Imp and Alfa to re-pass me. With every lap the electrics got worse with the tacho developing a mind of its own, dash lights going on and off and the engine stumbling, then eventually on lap 6 the Beetle finally ground to a halt, which was a shame as without the problems we were looking like a 15th place finish and a 2nd in class!

Back in the paddock we checked the wiring and tightened the battery terminals in the hope that it would help as our 1 hour race was fast approaching. We entered the 1 hour ‘Tourist Trophy’ race just for fun as it was clear, looking at the opposition that we were going to start (and finish!) near the back. The only cars that we knew we could beat were a 1500cc Sunbeam Rapier S3 and the 1600cc Alfa Guilia Sprint GT that i’d out-qualified in the earlier race. The rest of the cars were far too quick for the Beetle in its current state.

Then in qualifying it rained and the form book went straight out of the window. In the rain the Beetle on its crossply tyres was a real handful but with the weight over the rear wheels and less power than everyone else, we were able to get better traction out of the corners and found ourselves qualifying 11th out of 16 cars. Ahead of the Sunbeam Rapier, two 1600cc Alfa Sprint GTs, a 1500cc Ford Anglia 105E and a 3800cc Jaguar S Type!

In the race...to make sure that we could see where we were going, we switched on the heated windscreen (JK part No. J15327) Jeff did the first 30 minute stint in the pouring rain and had fun right from the start with the Beetle spinning its wheels then bogging down with the engine going off-cam as he backed off to get more traction from the cold tyres. This cost him quite a few places off the start, but once under way the Beetles wet weather performance and Jeffs experience payed off and he was soon back up to 11th place. Then over the next half hour he managed to pass a 1600cc Lotus twincam powered Ford Cortina...Things are looking good! Then it was my turn. The pitstop and driver change were quite slow for us, so as I left the pits the Ford ‘Lotus’ Cortina which had a quicker pitstop left ahead of me, so it was my job to retake the position. Unfortunately I hadn’t done many wet laps at Oulton, so I was quite cautious for the firat few laps in the changeable conditions, whereas Jason who was driving the Cortina for the whole race had already had 30 minutes in the rain already and knew where the grip was. I managed to match his lap times ‘just’, but there was no way I was going to be able to catch and pass him. The track was lethal in places and on some corners it was like driving on ice! There was so much water entering the first corner that the car aquaplaned as you approached what was normally a 70mph corner for the Beetle in the dry, which was focusing! The other corners that were bad were the Brittons chicane and druids corner, both which I had to do at less than half the speed that I was doing in the dry. One thing I was pleased about though was that we had no major electrical issues and despite the fact that the car has no door seals, no opening windows and our race suits and boots were damp, the windscreen stayed completely clear for the whole race which apart from being safer, certainly helped our lap times.

One thing that amazed me was that in the wet the track would change on every lap, so you never knew where the grip was. The trick in the wet normally is to drive on the sections of the track that aren’t regularly used as there is less rubber on these areas meaning the surface is more porous, allowing the water to sink into the tarmac, rather than sitting on top.

As the race neared a close, two things happened. Firstly I lapped one of the Alfas and the Cortina that I was chasing pulled off the circuit.

Relieved that we’d managed to stay on the track for a whole hour I crossed the finish line in 10th place, 47 seconds ahead of the Jaguar, 52 seconds ahead of the No.39 Alfa and over 3 minutes ahead of the No.30 Alfa. The winning car was a 4.7 litre Ford Mustang with two 1293cc Mini Coopers 3 and 6 seconds behind it! This is what I love about Historic Touring Car Racing, the David and Goliath battles featuring the 400+bhp muscle cars that are quick on the straights and small European cars that are quick in the bends.

To see the in-car movie of the Oulton Park HSCC race visit the Tech Tips section of the website. Sorry there’s no sound again, but the cameras microphone doesn’t seem to like the ignition system on the car and all you get is noise. (new ‘broadcast’ quality camera planned for next season)

The final HSCC points race for us is Brands Hatch this Sunday 13th Sept 2009 (although I’m tempted by a BeetleChallenge round also at Brands and an HSCC race at Silverstone, both later in the year)

I'm looking forward to Brands again and next week i’ll tell you all about it!

Ian

Mallory Park Race.

Motor racing is a strange mix of fun and frustration, and our second race held at Mallory Park in Leicestershire was no exception. After the elderly gearbox broke at our first race at Brands Hatch, we quickly had a fresh one built and were looking for a little extra speed going into Mallory.

Unfortunately, as soon as I went out in qualifying it was clear that something was wrong...the 4th gear was far too tall!...so much so, that the engine was having trouble pulling it. This was not good as Mallory Park is a fast track and 90% of the lap is 4th gear. It turns out that the top gear that was installed was the lowest gear available in the short time we had between races and the gear that we need is an unusual one and is a special order item from the states. (our gearbox is quite and unique specification in that it uses a Type 2 Bay Window crown wheel and is much lower geared than normal. Its far lower than even a drag racing box) As an example, if you were to put this gearbox in your standard 1300 Beetle, you would have a TOP SPEED of 55mph!

When the correct 4th gear is installed, we will have four close ratio, semi straight cut gears suited perfectly to the engine characteristics. Unfortunately we won’t see these benefits till after the seasons over. The result of this tall 4th gear at Mallory meant that we were quick out of the super tight ‘Shaws hairpin’, but everywhere else on the lap we got creamed!...even by much lower powered cars.

Qualifying ended with us being at the rear of the field with just a DKW 3=6 and an Alfa Romeo Guilia Sprint GT behind us. The race started well as the car pulls like a train in the first 3 gears. I managed to power passed the Mini Cooper S and Triumph 2000 MK1 off the start line and moved up 2 places before the first bend, but once in 4th gear I was open to attack down the straights and there was very little I could do to defend (weaving all over the track like they do in the movies is a definite no-no in racing and you will get excluded it you drive too aggressively)

On lap four, while approaching the 77mph ‘Gerards bend’ I spotted a shiny line indicating that someone had dropped oil or water on the track. The marshal correctly held the red and yellow striped ‘oil flag’ out to warn me, but there were a pair of marshals standing directly behind the flag wearing bright orange overalls, making it impossible to see until it was too late. The result was that the rear of the car stepped violently to the left. I managed to catch it but then the rear stepped to the right. I corrected, but I was running out of road and the tyres had no grip, so I decided it was better to stop fighting it and go through the gravel trap. I could have tried to keep it on track, but the car would have probably hit the gravel sideways and either rolled or at best, got stuck. There was plenty of run-off, so I took the safer option and rejoined the track dead last.

It took a couple of laps to get back up to speed, but I was soon gaining fast on the DKW and Alfa Romeo once more and looked like finishing in my starting position, but annoyingly caught up with them just as the race finished!

Despite the gearbox frustrations and going off track we had better luck than the Mini Coopers that we share the 1300cc class with. One overheated and the other, driven by Roger Godfrey backed his car hard into the guardrail just after ‘Gerards’ whilst avoiding a spinning Alfa Romeo. Both the Minis Misfortunes meant that once again we were gifted a class win (2 class wins in only our second race)

The good news is we weren’t far off the pace of the similar engine sized opposition in the first 3 gears at least and this showed at the start where, off the line the Beetle went from 0-60mph in 6.5 seconds and 0-80mph in 12.5 seconds...All this from a 1285cc engine that has more power to come and hasn’t been on a dyno or rolling road yet! We also got officially weighed at the track and found the car to be 55kg heavier than the Minis. If we drop the weight of the car by 7% (which is possible) to get to the class minimum figure we can (if the motorsport magazines are correct!) reduce our lap times by 3.5%. This would have made us two seconds a lap quicker at Mallory and (theoretically at least) put us around 3 cars further up the grid by weight reduction alone. Think how much modern British Touring Car drivers complain when they have to carry an extra 20kg of success ballast....We were carrying an extra 55kg and we’ve got less than half the power of a current BTCC car!

If you’d like to watch the complete Mallory Park race (from the drivers seat!) go to our ‘Tech Tips’ section, where you can watch the in-car footage. We will be adding more in-car race movies in the next week or so as the next race is this August Bank Holiday at Oulton Park in Cheshire which is a terrific twisty track that will suit our car better. We are entered in two test sessions, a 20 minute HSCC points race and a 1 hour, 2 driver ‘Tourist Trophy’ race.

Changes to the car since Mallory are small, but we’ve added a 3rd oil cooler (oil temperatures have been 120 degrees in previous races and we’d like to get them down to 85-90 if possible) and we are going to try adding a power pulley in testing and if the engine temperatures aren’t too high we will keep this pulley on for the races as it gives us an extra 7-9bhp at 8000rpm which will benefit us on the exits of the corners, up the hills and help pull that tall 4th gear.

Future plans are a lower 4th gear, lower weight, set the engine up on a rolling road, add a new pedal box with full brake bias adjustment and replace the standard cooling system with a large electric fan (the standard cooling fan and alternator wastes approx 14bhp@8000rpm!) The electric fan and small race alternator hopefully won’t use more than 4bhp. These improvements will come too late for this season, but they will make a huge difference to the performance. With this in mind we will be right on pace in 2010 and we’ll be able to take the fight to the other cars.

Next week I will let you know how (and show you how) we got on at the Oulton Park Gold Cup.

Bye for now.

Ian

Brands Hatch Grand Prix Circuit (Race Day)

Race day started early with qualifying. The original goal for the weekend was to not qualify last, but as the gearbox was broken and we only had 3rd gear, this was looking optimistic to say the least. The Mini Coopers that we share the 1300cc class with, normally lap the full Grand Prix circuit between (1:55) and (2:04) and the best that we had managed two days earlier in testing (with only one gear remember) was a (2:17).

The engine was 10bhp down on what it will finally make, but was running really sweet. The only problem with extracting large horsepower from a small engine is that it only delivers large horsepower over a very narrow rev range, plus our flywheel weighs virtually nothing which means it revs like mad but has no way of maintaining any kind of momentum. With our engine, the power band is between 5500rpm and 8000rpm. Below 5500rpm the engine goes ‘off-cam’ and suffers a huge drop in power, and I found this to my cost when trying to leave the paddock. At Brands the paddock where the majority of the race cars are kept is at the bottom of a hill and you have to climb this hill to get to the race track. On the first attempt the Beetle didn’t have enough power to get up it, which was a bit embarrassing! I got near the top of the hill (in first gear) but the car just couldn’t do it. And as the car no longer has a handbrake, I had to roll back down to the bottom and have another go (It will do it, but you have to rev the nuts off it!) People have said to me that I should make the car road legal, because it would be really cool to drive a 130bhp 1300cc Beetle on the street, but in reality it would be impossible to use on a daily basis for this very reason.

So no good on the road then....On the track though, it’s a different story. This Beetle may only be a 1300, but it has the power to weight ratio of a Lotus Elise and as long as you stay above 5500rpm it’s a seriously quick car.

Unfortunately for me at Brands, all I had was 3rd gear, so every time I exited a corner the revs would drop as low as 4500rpm which meant that I had to wait for an age, for the engine to gain that extra 1000rpm before the cam and the power came in. This was destroying my lap times (7 seconds per lap to be exact) and during the race I was going to be a sitting duck out of the bends.

Never one to give up, I decided that the only way to stop the engine from going off-cam was to take a brave pill and enter the corners at the highest speed that the car could manage. This tactic clearly worked as the laptimes tumbled during qualifying: (2:16.5) (2:13.6) (2:11.0) (2:10.9) (2:10.7) then finally a best of (2:10.2) at an average speed of 63.5mph. This put me predictably 26th place on the grid, but amazingly I was only a tenth of a second behind the slowest Mini Cooper and ahead of three other cars. firstly a 5 litre Ford Falcon Sprint which had issues in qualifying and a pair of 1500cc Ford Lotus Cortinas....We didn’t qualify last...yay!!

The big question now was, what could I do in the race? At 5pm I found myself on the grid for my first ever race. The race had been shortened to 8 laps to allow the Historic Formula One Cars that followed enough time to finish their race before the 6pm curfew, so I had to race hard from the getgo if I was going to make an impression on the other cars.

Unfortunately, not being used to the lights I was caught napping at the start, but still managed to pass the 84 Mini before the first corner at Paddock Hill Bend. I myself was passed by the pair of more powerful Lotus Cortinas and the Ford Falcon. Down Paddock Hill Bend and up Hailwood Hill I managed to carry more speed and re-passed the 34 Cortina and take the inside line into the tight Druids hairpin, this was where I got baulked by the other Cortina which allowed everyone to pass me (Told you i’d be a sitting duck out of the bends...”If only I had second gear!”)

As I turned into Surtees and joined the long Pilgrims Drop straight, I passed the 85 Mini Cooper which had developed electrical problems. I was pulling 8000rpm as I braked for Hawthorn Bend and by the time I had reached Stirlings Bend I was back up behind the 34 Lotus Cortina. What followed after that was 6 laps of dicing with the Cortina. The Beetle was much faster through the corners and better under braking, but the Fords 1500cc Lotus Twin Cam engine gave it better speed on the straights. On a typical lap I would be ahead of the Cortina through Graham Hill Bend then get overtaken along the Cooper Straight. I’d regain the position through Westfield or Stirlings Bend and then get passed before clearways, then get ahead of the Cortina again through Paddock Hill Bend and up Hailwood Hill.

Unfortunately all this fighting meant that we were slowing each other up and the rest of the field were able to pull away from us. On the final lap I got baulked again at druids, dropping the car off-cam again and couldn’t catch the Cortina before the checkered flag, so I finished up stone dead last.

Now this may seem like a poor showing, coming 24th out of 24 finishers, but actually the race proved to be a great success for us. Firstly we finished which is important, and finished only 6 seconds behind a Lotus powered Ford in our first race and this was despite the hindrance of having only one gear. I even managed to get my lap times down to a (2:08.9) during the race which would equate to a (2:01) lap if I’d had all the gears, which could have put us eight cars higher at the finish, quicker than two 1500cc Ford Anglia 105Es, three 1000-1150cc Hillman Imps and three 1500cc Lotus Cortinas. Plus there were a lot of more exotic cars that raced over the weekend who couldn’t run as quick as a (2:09). These included a 1600cc Porsche 356A, 1600cc Alfa Romeo GT, Lancia Fulvia, 4.5 litre Porsche 928, Triumph TR4, Triumph GT6, 3.8 litre Jaguar E-Type and 4.7 litre Corvette Stingray and we were quicker than all of them!

Then, just to round the weekend off, we were told that the 80 Mini had also broken down and the 84 Mini had gone off, handing us the class win, trophy and maximum points in our first race....It’s not how I want to win, but as the saying goes “to finish first, first you have to finish.” Any future wins (I’m hoping) will come from speed rather than reliability.

The best thing to come out of the weekend for me, is the knowledge that the Beetle is competitive straight out of the box. We are currently 6 seconds off the pace of the fastest lap time recorded by a Mini Cooper S on this circuit, but bare in mind that we haven’t had the engine on the dyno or rolling road yet. This and a power pulley will give us at least another 10bhp. The new Cogbox gearbox will be much better suited to the engine and will keep it above 5800rpm for the whole race. Then we can go another 15kg lighter and we haven’t even touched the suspension set-up yet. All these factors and the fact that I will get quicker as a driver mean that we will be running (1:55 or 1:56) laps on this circuit this time next year which will match the best of the Minis (and to put it into perspective) match the 4.7 litre Ford Mustangs and late 60’s and early 70’s 2.0-2.2 litre Porsche 911s too!

Since Brands Hatch I have taken the car to BugJam for some RWYB action. Unfortunately it ran like a dog. It was misfiring for the whole 1/4 mile (possibly moisture getting to the exposed carbs on the trailer getting up there) I didn’t have time to sort it, so the car ran a best of 17.2@77mph using only first and second gear...yep! 77mph in 2nd!!

The car will be on display at the Just Kampers Open Day this Saturday (1st August 09) and it’s receiving it’s new gearbox on Monday, then it’s our second race which is at Mallory Park in Leicestershire on Sunday 9th August, where we hope to be somewhere in the middle of the pack now that the car is fighting fit, rather than the back of the field and we will be fitting an onboard camera for the first time, so that you can watch the whole of qualifying and the race via the Just Kampers website.

Looking forward to that...so, sit tight and I will tell you next time how we got on at Mallory.

Cheers!

Ian  

Brands Hatch HSCC Superprix Testing

Well, our first race weekend has been and gone....And what a weekend!

It actually started on Thursday afternoon a Llandow circuit in South Wales. The plan being, to get there for lunch but we had problems with the brakes which had to be sorted first and so we arrived at the track a 4pm, just as the rain started. So the first time the car would hit the track would be in the wet! We had 2 hours tracktime to check the oil pressures, oil temperatures, get the engine run-in, check for leaks and generally make sure everything worked as it should.

I didn’t even get to the end of the first lap before there was a problem. Whilst braking hard for the tight ‘bus stop’ bend, there was a horrendous judder and noise from the front! After getting the car back to the pits, what we found was not a mechanical fault, but that the wings were biting chunks out of the front tyres when the nose of the car dropped under braking. As we were tight for time, we simply raised the front suspension by a couple of inches. Not ideal for a race car, but it did solve the problem and didn’t appear to effect the handling (in the wet at least).

So how did a swing axle Beetle handle on crossply tyres in the wet?....Staggering! You could throw the car into a corner (even through puddles) and it would stick. There was a tiny bit of understeer, but after a few laps I had even forgotten that it was wet! The rear didn’t lose grip once in the whole 2 hours, you could floor the gas mid corner and the car would just catapault out of the bend with no slide or traction problems!

A couple of rounds during the season are 40 minute, 2 driver races with a pit stop half way through for a driver change, the next one being the Oulton Park Gold Cup on the August Bank Holiday weekend. Jeff Culkin, as an Ex Just Kampers employee with a long racing history has been charged with sharing the drive. Jeff is used to racing Alfas and MG Midgets, so now was a good opportunity to give him his first experience of a rear engined car.

Jeff had his doubts as to whether a Beetle was the right choice to compete in Classic Touring Car racing, so having driven the car myself I was keen to see he would get on with the car. Jeffs never driven a Beetle before, but he settled into it very quickly and despite the damp track was putting in some good laps and when he came back in the pits, the smile said it all.

Before we knew it, the 2 hours was up, but we’d learned a lot about the car. Pressures and temperatures were fine, the engine was great, the handling was far better than even I was expecting and it was clear that GAC had built one hell of a car.



Early the very next day, we were at Brands Hatch for a full days testing on the full Grand Prix circuit. This consisted of 4x 25 minute sessions spread over the day. With no other saloons testing that day, we were put in with the HSCC 60’s and 70’s ‘Roadsport’ cars which are GT cars like Porsche 911, Porsche 928, Lotus Elan, Lotus Europa, Marcos, Morgan, Corvette Stingray, Jaguar E-type etc. These sessions gave me a chance to learn the circuit and as the day went on, gradually bring the speed up and try to see just how fast this Beetle was going to be.

The lap times that we are aiming for are the ones set by the Mini Coopers that we share the 1300cc class with. On the Brands Hatch GP circuit the Minis are lapping between 1:55 and 2:04, so off we go for the first 25 minute session.

With instructions to stay below 6000rpm on the new engine I went out on the track. The roadsports cars were fast! so I had to keep my eyes on the mirrors, but interestingly they weren’t much faster in the bends and in fact on one corner in particular (Sheene Curve) I could actually make up time on the Lotus’s and E-types! And amazingly I found that I could out brake every single car on the track, not by a little, but by around 3 car lengths!...These CSP brakes are awsome!

Soon the 25 minutes were up and I headed back to the paddock to see what my times were. 2:30 I was told! Hmmmm 35 seconds off the pace....”WHERE AM I GOING TO FIND 35 SECONDS?” This was worrying. Maybe Jeff was right...perhaps a Beetle was the wrong choice after all.

The brake pedal was a bit spongy in that session, so that was adjusted and it was time for the second 25 minute session. This time I was allowed to use 7000rpm, and what a difference!...The engine suddenly came alive! It was clear that this engine liked to rev. It pulled so much stronger out of the corners and I was having to brake much harder due to the higher straight line speeds. Best lap time 2:08!...I’d knocked 22 seconds off my previous time, we’re getting somewhere.

The 3rd session didn’t go so well. For a start I had my first spin. This was at Westfield Bend which is the only corner that the car didn’t feel comfortable taking. Its a fast right hander which drops steeply into a large dip which makes the car light and unsettles the car. I was approaching this corner and I could see 3 cars coming up on me in the mirrors. I kept to the racing line and stayed on the gas like you are meant to, but unfortunately found a Lotus Elan right next to my door just as I was turning into the corner and with another Elan and a Marcos running directly behind it.

Squeezed out, I had to reduce the throttle and turn a little tighter to stay out of the gravel, unfortunately this coincided with the car going over the brow of the hill. The combination of all these factors and the weight of the engine over the rear proved too much for the rear tyres and even with an arm full of opposite lock, it was too late. I was sent spinning two full revolutions down the hill. I’ve seen too many spun drivers collected by following cars and didn’t want to be one of them, so thinking quickly as the spin started, I depressed the clutch pedal, so that the engine didn’t stall and I was soon on my way again, thankful that I had stayed on the tarmac and not buried it in the wall or gravel trap.

Lesson learned, I carried on putting in the laps. This time I could use 7500rpm and the car felt quicker again, but second gear, that had been jumping occasionally earlier was now jumping out of gear all the time which was on 5 of the corners and it got so bad I had to use 3rd gear instead. The result a 2:15 lap was the best that I could do. The gearbox was costing us at least 7 seconds per lap.

We decided to skip the 4th session in order to save the gearbox for the race on Sunday. We were going to need a miracle to have any success in the race.

Well...a miracle is what we got!..and I’ll tell you all about it in a day or so.

Stay tuned

Ian

Well, It's the Wednesday after our first race and I thought I would give you a little teaser to let you know how it went. We had 3 Mini Coopers to deal with in the 1300cc class and we broke the gearbox in Friday testing and had to do qualifying and the race with only 3rd gear, so how do you think it went?

How about a class win, trophy and maximum points in our first ever race (with only 1 gear!)

This car really shifts! There was a Porsche 356A running a mildly tuned 1600cc super 90 engine and we were lapping 10mph faster and we could out corner many of the cars and outbraked ALL the cars on the track. In the next day or so I will write a complete Blog telling you all about our first weekends racing.

Bye for now

Ian

This was meant to be (part 2) of our suspension and handling piece, but we will have to put that on the back burner for a couple of weeks.

Reason being...WE ARE RACING THIS WEEKEND..Yay!!

After a difficult birth, we've now reached a point where we can get the car on-track and see if all the effort has been worthwhile. A big thankyou must go out to Andy and his team at the Farnborough VW Centre (01252 521152) for rewiring the whole car at such short notice and putting in some long hours on our behalf. We wouldn’t have made the race without them.

So the plan is pick the car up from GAC (vwracing.net) tonight, drive down to Llandow circuit in Wales for an afternoon shakedown tomorrow (Thursday 2nd July) to run the engine in, check the oil temperatures and pressures and generally make sure that everything works as it should.

The following day we are at Brands Hatch for a full days testing and then the race is this Sunday (5th July)

I would just say...Don’t expect too much from this race, as we haven’t had time to get it on a rolling road, plus we haven’t fitted a power pulley yet, so we could be 10-15bhp down on power. So this weekend is all about just finishing the race and keeping our eyes peeled for any ‘new car gremlins’ that may occur.

We will be in a better position at the next round at Mallory Park when the car is better sorted and after I’ve squeezed more track time under my belt.

So if you’re in the Kent area on Sunday, pop down and say hello....I’ll be the lanky bloke walking round the pits looking like he doesn’t know what he’s doing!!!

And if you can’t make it. Don’t worry...It’ll all be covered in next weeks blog!

Wish me luck!

Ian

I was hoping to be reporting on our first race by now, but as always with these things, something always crops up.

GAC who are preparing the Beetle had their two Championship leading Formula Vee single seaters crash at the last round, so the Beetle had to go on the back burner while the two Vees were rebuilt.

This means we’ve got a frantic 2.5 weeks, before our first race at Brands Hatch on July 5th.

For the moment, I am kicking my heals, so I thought we would cover suspension this time round...And the next round as it happens, as this is such a huge area to cover, we are going to split it over two blogs, starting with the basics, and then in the second blog we will run through what we have done to make the car more competitive (we hope!)

Suspension (part 1)

You can have all the power in the world, but if you can’t get it round the bends, you’re never gonna to get your mits on that plastic trophy! This was amply demonstrated last weekend at Castle Combe circuit where a 4.7 litre, 400bhp Ford Falcon got out-qualified by a 998cc Hillman Imp. The rear engined Imp then used it’s light weight and superior handling to pull away from the muscle car during the race despite only having a quarter of the power.

The Mini Coopers are our main opposition in the 1300cc class, and looking at the weight, horsepower and braking, we should be evenly matched. But when it comes to suspension, I think the Minis may have the edge on us....Time to start boning up on books, magazines, the internet and speaking to current and past Beetle racers, to see what can be done to improve the Beetles notoriously tricky handling.

This proved an interesting exercise, as no-one seems to be able to agree on what makes a Beetle handle.

Now...The bloke down the pub will always tell you that to “make ya motor andle” you need to lower it as much as possible and stiffen it as much as possible.....But it’s not quite as simple as that!

Stiffening the suspension will not, in itself increase grip...In fact, if you did nothing other than stiffen the suspension, the car would actually have less grip! A lowered and stiffened car handles better mainly due to the lower centre of gravity, reduced body roll and reduced weight transfer. Stiffer springs will also help reduce body roll, but at the expense of grip. The main reason for stiffening the suspension is purely to stop the lowered car from hitting the bump stops and bottoming out....Put simply, we need to get the car low, but at the same time use as soft a springing as we can get away with.

Then we need to get the balance of the car right. This means that the front and rear of the car have equal amounts of grip. If the front of the car loses grip before the rear, the car will not want to turn into the corner, this is known as ‘understeer.’ If the rear of the car loses grip before the front and the car trys to swop ends this is known as ‘oversteer.’

In order to improve the Beetles balance we need to first relocate some of the cars heavier items, such as battery, fire extinguisher, drivers seat, oil coolers etc, to shift some weight onto the front tyres. The extra weight up front will also help to get some heat into the front tyres, making them stick, and reducing the chance of understeer. After this it’s all about adjusting the dampers, front anti-roll bar, rear z-bar and tyre pressures until we’ve got the car the way we like it.  

Now...everyone knows that Beetles ‘oversteer,’ this is caused by the swing axle rear suspension design, coupled with the engine hanging out of the back like a giant pendulum. VW reduced this tendancy to oversteer in the early 1970’s by adding a z-bar to the rear suspension which allowed the rear springs to be softer, improving rear tyre grip. What most people don’t know is that Beetles also ‘understeer.’ This is another result of the rear engined layout. The lack of front end weight means that the front tyres cannot generate enough grip. Early Porsche 911s had the same problem and Porsche got around this (crudely) by slapping weights behind the front bumper.

The old ‘Beetle Cup’ cars and many Beetles competing in the new ‘Beetle Challenge Championship’ (see www.beetlechallenge.com) actually run very low, very stiff and with very little suspension travel, which interestingly goes against everything that we’ve said earlier! (Told you knowone can agree in what makes a Beetle handle!)

We on the other hand are running our car relatively soft with mild lowering, so we will have a good deal more body roll than the Beetle Challenge guys, but there is method in our madness. And it’s not a case of we are right and the Beetle Challenge guys are wrong or vise-versa.

After all...some of these drivers have been racing for many years and know their cars inside out. The reason we are running our car softer is because we have to use racing tyres developed in the 1950’s and 60’s when race cars went round corners on their door handles! These tyres are better suited to softer setups.

Take a look at the current HSCC Historic Saloon Car Championship leader Dan Cox’s Ford Lotus Cortina below. It has the softest suspension of all the cars out there and spends most of the race on 3 wheels, and yet he’s leading the Championship by a country mile (and having more fun in the process, it has to be said!)

We are setting our Beetle up the Dan Cox way. Then over the remainder of the season we will fine tune the car to get the best out of it.

If you want to see some proper racing, check out these youtube clips from the 1960’s. It puts modern Touring Car Racing to shame!

Not sure about the sound track on the first one and Damon Hills dad ends up parked up a tree, but lots of 3 wheeled action...The second clip features a much better soundtrack plus a sickening Mini crash...And commentary by Mr Cholmondley-Warner it seems!!

http://www.youtube.com/watch?v=pYQKKlir6sY&feature=PlayList&p=28D6D1B5B961C211&playnext=1&playnext_from=PL&index=5

http://www.youtube.com/watch?v=bWp-0TuY4Sk&feature=PlayList&p=28D6D1B5B961C211&index=6&playnext=2&playnext_from=PL
 
With the Historic Touring Car racing running at much the same tracks as the Beetle Challenge cars this season, we will be able to compare lap times. Their ‘stiff’ cars against our ‘softy’.....Place your bets everyone, this should be interesting!

Next time, we will show you all the tweeks that we have made, in order to keep up with those pesky Minis.

Bye for now

Ian