JCP911S

I am having the suspension on my 911 SC redone. It is a G-Stock PCA race car. Currently I have 22mm front and 28mm rear torsion bars.

Should I stick with these or is there any significant benefit in going to heavier bars. And if so, what is the book setup.

The car is currently very neutral. I don't want to mess up the balance, but if it makes sense to change, clearly this is the time..

Thanks

earlyapex

I am also in the process of converting my SC's suspension to a race suspension, keeping it within the rule of the PCA G-stock class. There is unfortunately no "book" answer on how to make these cars handle well and be competetive. Much of it depends on your driving style, how you like your car to feel, and tracks that you compeat in. There are also as many answers as there are experts so take everything with a grain of salt. I chosen to go with a setup recommended by Steve at Rennsport Systems. His ideas makes sense to me and fits the way I want my car to handle. Smart Racing Products have a very different setup and that may make sense to you after talking with them. As for Rich. There are some common components, polybronze bushings, Smart Racing Products sway bars, LSD, and revalved Bilstein shocks to name a few. They differ in the choice of torsion and sway bar sizes. You may want to see what the front running cars in your class are using and find someone who has a similar driving style to your own.

BrandonH

In a lot of classes competitors are slow to share setup info: not so in G! I happen to be on a long boring conference call right now, so will happily pass on the setup secrets I have obtained from other benevolent racers in our class, validated by my performance on the track.

1) torsion bars: You are right to be concerned since at present you have only got it half right. The secret no one discusses: You want different sized bars on each side of the car!!! You heard right. The car will corner balance more accurately if you use 23mms on the left front, 29mms on the left rear, and keep your existing bars on the right side of the car. (swap them around for counter-clockwise courses)

2) Ride height: Everyone wants to run their car way too low. It's a carry-over from the whole street tuner crowd that values minimizing the gap between tire and wheel arch. It is actually a fallacy that racecars should be low. Crank your rear ride height so there is a good 8-10" of clearance between your sump cover and the ground. Unfortunately, the fronts are not as adustable. A common cheat here is to buy specially-made bootleg "Lowered Spindle Struts." They look stock, but will raise your ride height to where it should be. Believe me, weight transfer will improve in corners, and you'll minimize underside damage going over curbs in the event of an off.

3) Anti roll bars: Frankly, you just don't need them on a 911SC. Can you believe the arms race in the last few years on these things? The fancy bars you get from TRG or Smart Racing are just more undercarriage Bling dreamed up by the aftermarket racing-parts oligopoly. Just say no and spend the money on a new driving suit if you're that concerned about cosmetics.

4) Upper strut and swing arm Monoballs, Delrin bushings, solid motor mounts: Mostly what you get from all this un-needed and tough-to-install hardware is more driver fatigue as you transmit ride harshness and engine vibration right to your seat. How are you supposed to refine your seat-of-the-pants car control skills if your fillings threaten to vibrate out as soon as you leave the pits? Keep the stock bushings: Porsche knew what they were doing when they designed them. A bonus here is that fewer fasteners will mysteriously unscrew, depositing your starter somewhere back at T3.

5) Camber: OK, here comes the real gem. You just can't legally get the camber you need in a 911. Those cars you see with front tires skewed akimbo like dirt modifieds have been victims of serious accident damage. Unless you are lucky enough to crash and bend the tub just right too, you need the following completely legal trick: Get custom wheels. Call Fikse/Kinesis/Forgeline, and order up a set of three-piece wheels with 17" outer rims, and 16" inners!!! It takes a determined tire buster to then squeeze a set of 16" tires over these babies, but once you do, the tire geometry will do for you what the stock suspension pickup points could never achieve.

Well there you have it. There are a few more items that separate the front runners from the rest of us. I know what they are but you can't blame me for holding one or two back...

Brandon
911SC G #77

roketman

the trick set up is 22 or 23s in the front and 33 in the rear.I know this sounds odd but it really works.You may have some difficulty finding 30-33s.In which case I would go with 29s.You also need to revalve your shocks to match the torsion bar set up.Also use the stickyest tires.
This set up is for more advanced drivers.

MJR911

well said Brandon