i don't think it's the greatest idea:

1) if you want to go with a shorter tire, it may help acceleration a bit. not much, though.
2) your speedo will read higher than you are actually going. you will put more miles on the car than you actually travel. get a yellow box to fix this.
3) i would go with a 245mm wide tire in the rear. i wouldn't sacrifice grip for slight acceleration improvements you won't feel much.

solution: go with a 245mm wide tire in the rear. get a higher fd gear. yellow box.

the stock s02's that came on the ap1 were very wide for a 225mm tire. they are comparable to a 245mm tire. just keep that in mind.

 

It might help you accelerate faster but handling would suffer with a more narrow contact patch and a 35 series tire is so thin you'd have a very harsh ride and the first pothole would dent your wheel rim.

 

I don't think you'll feel quicker with any smaller tire that'll fit on the S. Lighten the car, 200# is reachable, and you'll feel a difference.

 

This was tried by a user over in Europe, I actually just read his posts just the other day. He said that he actually ended up being slower in the 400m.

 

Lower profile tires like that will change the gearing to shorter gears. Looks funny and all but 34 profile tire compared to a 40 or so will shorten things up a little bit and improve off the line acceleration.

 

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