Track tires for 97 993

[Mimik]

Just bought a 97 993 and I am looking for track tires. I wanted to ask if the 275/40 17 on the back will rub? Was planning to put the 225/40/17's on the front. Standard was 205/50/17 and 255/40/17. Appreciate the help, Mimi

[Don Plumley]

Congrats and Welcome. You may be interested in our 993 forum and the Track forum.

On my 993 I run 235/45 17 in the front and 275/40 17 in the rear. I've rolled the fender lips and moderately aggressive neg camber. Keep the rolling radius pretty close or you may trigger ABS problems.

Don

[Bill Verburg]

Assuming that you still have the stock 7 & 9 x17s thesm you can use 225/40 and 275/40 tires but the wheels are on the narrow side for the tires and the 275/40 is an awfull tall tire. As Don mentioned you want to kwepp the rolling radius f/r pretty close.

Toyo makes R888 & RA 1 in 215/45, 225/45 and 235/45 and 235/45 for front and 255/40 and 275/40 for rear.

I would use 225/45 and 255/40 on those wheels

In 18 MPSC 225/40(or 235/40) and 265/35 on 8(or 8.5) & 10 is a very good choice

[aigel]

I have the 235 and the 275 RA's on 17 stock wheels.

George

[Scott at Pelican Parts]

Hi Mimi,
Mike's brother Scott, here. Welcome to the forum -- sounds like a great project! Check out Don's website where he outlines his version of what you'll be doing, after you begin tumbling down the slippery slope.

http://www.plumley.org/porsche/build.htm

Cheers!
Scott

[Mimik]

Thank you all for the information, very helpful! I am thinking of going with Toyo R888's 225's on the front and the 255's on the rear. I am sure I will be back on here once I get the car with lots of questions. Mimi

[aigel]

255 isn't a lot of meat for the rear of a 993. Yes, the wider tires are taller and the sidewall may not be as stiff. I have to say though, my 993 sticks very well with the 275. I think the contact patch may be a bit more important here and make up for sidewall stiffness and acceleration. Unfortunately there is on 265, which is ideal.

Cheers, George

[Mimik]

Okay, new question. Exhaust and headers? Any input?

[Bill Verburg]

Originally Posted by aigel

255 isn't a lot of meat for the rear of a 993. Yes, the wider tires are taller and the sidewall may not be as stiff. I have to say though, my 993 sticks very well with the 275. I think the contact patch may be a bit more important here and make up for sidewall stiffness and acceleration. Unfortunately there is on 265, which is ideal.

Cheers, George

W/ modern race oriented rubber the need for really wide tires is greatly reduced. The contact patch shape is far more important than the area. I agree 265/35 is just about perfect.

The effect on gearing per se is not important on track except as it shifts the relationship between speed and revs in a gear. Sometimes it helps, sometines it hurts.

Gearing form a taller tire will always hurt in stoplight drags.

[Bill Verburg]

Originally Posted by Mimik

Okay, new question. Exhaust and headers? Any input?

stock headers and Fabspeed or Cargraphic cat by pass and stock mufflers is a great combination

above w/ RSRs instead of stock mufflers is far noiser but if that's what you want it's good too.

It's generally not advantageous to go to full headers unless you get some nice lumpy cam as well.

[aigel]

They got the 993 exhaust right from the factory. Certainly none of the restrictions you may be used to from the 80s. My car only has some modified baffles in the stock mufflers for a little better sound. I don't feel it is choked by the exhaust. Modifying the stock muffler certainly is cheap.

George