Build my 944 S2 for the AutoX

[porsche1973911]

Build my 944 S2 for the AutoX

Hey all. I do not have faith in my 911 as an autox car and feel that my 1990 944s2 cabriolet has much more potential. The car is old but bodymotion serviced. I want to stay in stock class but hate my curbed design 90 wheels and all season dunlops. It also looks like my strut bushings have dried up. Here is what I need your help with:

Tires: Should I keep stock size of 205f/225r or upgrade to 225f/245r like some have done? Also any suggestions for a great summer tire with around 200 treadwear that will work great in an autox and on the street?

Wheels: I guess i have to stick with 7x16 and 8x16 to stay in the stock class right? What other porsche wheels or decent aftermarket ones can i swap in? any boxter wheels fit?

Suspension- ordering koni sport shocks and struts from pelican unless someone has a better idea that keeps me in stock class.

Engine: I have a k&n panel filter. would a cone intake help? I also plan on getting a chip. Weltmeister or Powerchip?

Cabriolet: Do I need any safety modifications since this is a softop?

Thank you all very much in advance.

[Born2bwild1191]

I would go with the wider tire, KONI suspension is always good, and i dont think a cone filter helps. Just changes sound IMO i didn't notice any power difference. I've never autoX'ed, so this is my unprofessional opinion. I'm sure someone else with way more knowledge about this will chime in....by the way, Welcome to Pelican forums, probably the most useful tool to owning a Porsche known to man

[porsche1973911]

thanks.care to elaborate on why i should go with the wider tire? The stock size would keep price and weight down a bit, which is always a plus. i just want to be sure that the upsize is worth it.

[Dantilla]

Read the rules!

In our local PCA region, a cone filter and an aftermarket chip will each bump you out of stock.

SCCA rules are very different.

[Dantilla]

By the way, I sold my S2 autocrosser, and now run a '73 911.

(Far from stock- It has a 3.2!)

[elirentz]

Most definitely can't upgrade the airbox or ecu in stock class with scca.

Pretty much the only mods allowed in scca stock class are

front swaybar
struts
catback exhaust
drop in filter
wheels
tires

definitely no ecu mods, springs, intake mods allowed

[porsche1973911]

Thanks but this is for NNJ PCA. they allow ecu mods, air filter mods, both front and rear sway bars, etc.

[andyshoun]

All things equal, a wider tire will allow you to generate higher cornering force. 20mm is not much of a difference and this can be easily made up with tire construction, sculpture and tread compounding. Given a good fit on the car I normally choose wider tires, but it will not make much difference. The trade offs are cost and hydroplane resistance. The thing to watch out for is a change in the tire diameter or revoluctions per mile (affects your gearing and speedometer function).

Ummm, if that sounds like a bit much, it is because I work for Michelin and design tires for a living.

[porsche1973911]

It seems like i have more choices in the 205/225 combo. That is also the combo i run on the 911 so I could always transfer the tires if needed. I am hesitant to go bigger but the word is that bigger is better so i might give in.

[Techno Duck]

I auto-x'ed my '87 n/a for 4 years before selling it in favor of a 951. Wider tires are a must especially with the low end punch the S2 has. I recommend finding another pair of 8'' D90's (which is what i assume you have on your S2 now). Or any set of 16x8 late offsets (968 5-spokes and phone dials). Throw 245/45/16 all around on and rotate to all 4 corners to maximize tire wear. This is a great neutral combination. I used 225/45/16 v710's on my '87 and the balance was fantastic. The 944 platform greatly responds to wider rubber upfront as they understeer with factory sizes.

There are tons of suspension options. Koni's are not bad but dont expect to be a champion or anything. Stiffer springs are a must as the 951/S2 are really softly sprung, my 951 and my friends (both stock springs with Koni's) drag the corner of the undertray on the ground when cornering hard. You can go with the GroundControl coilover sleeves and run smaller diameter HyperCoil springs or go with the Weltmeister 200lb or 250lb springs. The Weltmeisters will cause about a 1''-1.5'' drop, there are spacers available to maintain stock height (but a little lower than stock is good). The GroundControl sleeves basically let you set it at whatever height you want. With either option you can correct for a lower front by dropping the rear end using the spring plate most of the time. Just be careful with spring rate choices in the front, too heavy front springs will cause mega understeer. I used 200lb fronts and stock rear torsion bars on my '87 and the car handled pretty neutral with slight understeer at the limit that could be dialed out with tire pressure and rear sway bar choice. If you want heavier front springs, you need to do the torsion bars in the back also (not a job for the faint of heart).

For sway bars, up to the 30mm front 968 and adjustable 19mm rear.

Ive done a few NNJ Auto-x's a couple years ago when i was real into auto-x. Last i heard no events at the Meadowlands anymore which sucks. If your not far from Long Island, check out the Metro NY region's auto-x events. We have a bunch at Nassau Collesium and Tobay Beach (which is probably one of the best venues in the tri-state area).

[porsche1973911]

Thanks for all the good info duck. I think im going with 225 all around as that is the best compromise for me. I will probably move up to bigger sway bars eventually. I wonder what size i have stock as it is a cabriolet. Im not really close to LI and the traffic there is enough to keep me from ever driving stick near it but thanks for the heads up.