i'm thinking about DSP next year, and have been considering various tire sizes. going with a shorter overall diameter will help acceleration at the expense of ultimate speed in 2nd. i'd like to avoid having to shift into 3rd on all but the longest courses.

it seems like my integra rs can get to 59-60 at redline in 2nd now. that's on 195/60 14 falken azenis. not using their specs, but just this size generically, i get a diameter of 23.21"

i was originally thinking about 13s, but now think the wheel money would be better spent going towards a LSD, and possibly a new clutch and lightweight flywheel.

so the main sizes under consideration are the 195/55 14 and 205/55 14 victroracers. the 195 gives overall diameter of 22.44" while the 205 has 22.88"

what are the tradeoffs between grip associated with the increase in width, vs. gains in acceleration? what type of 2nd gear top speed would i be looking at?

thanks for all the help,
phil

 

tirerack.com

all the formulae are there.

nate

 

Assuming your quoted diameters are right (check at tirerack.com as suggested) the difference in diameter is directly proportional to the difference in top speed. So if there's a 10% diff in diameter, there'll be a 10% diff in speed so from ~60 to ~54.

Just do the math for the sizes you're looking at.

 

cool, thanks. i figured it would be that simple, but i didn't want to assume anything.

 

Check out this calculator

http://www.venommotorsports.com/libr...calculator.asp