Best tire size for SS/TC for road coarse track
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Best tire size for SS/TC for road coarse track
What is the optimal tire size that I shouldget with stock suspension, looking at dunlops Dizerra 235/40, but will 245 work even better on stock rims, or is 245 to much for road racing. I am basically looking for best tire size for optimal road coarse racing on stock rims. Also do have to take it to 245/35 for clearance? Also even if I go 235, do I need to go down to 35 series?
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From: Scranton, PA
What type of racing? Lots of HPDEs, time attack in certain classes don't allow R-comps. And if your just learning I wouldn't recommend them anyway. 245s work fine as long as there 245/35s. That's what I'm running right now. As far as I know the only good extreme performance tire in that size are the Kumho XS.There the most sticky out of the bunch but, aren't as good in other areas. Sidewalls are a little softer, and don't like the cold or wet as much as say the dunlop starspec or NT05. The advans and re11s are also great but do you really wanna pay $50 more per tire for similar performance? If I didn't go with the 245 I would have stuck with the stock 225. Your gonna gain more with the smaller diameter than you are with the less than 10mm more rubber on the road. there i'm done 
BTW, check it out that thing looks like it's 4 wheel drive! I'd own it with some 44" boggers on it.
BTW, check it out that thing looks like it's 4 wheel drive! I'd own it with some 44" boggers on it.
Last edited by jboogie; Jan 6, 2010 at 11:57 PM. Reason: Automerged Doublepost
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From: Rochester, NY
where will the tire rub?
Are 225/40r18 and 245/40r18 the same height.... the 245 is just wider? Why would making the tire more low profile make a difference for rubbing (35)
Are 225/40r18 and 245/40r18 the same height.... the 245 is just wider? Why would making the tire more low profile make a difference for rubbing (35)
Last edited by rckrz6; Jan 13, 2010 at 09:11 PM.
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From: Tampa
What is the optimal tire size that I shouldget with stock suspension, looking at dunlops Dizerra 235/40, but will 245 work even better on stock rims, or is 245 to much for road racing. I am basically looking for best tire size for optimal road coarse racing on stock rims. Also do have to take it to 245/35 for clearance? Also even if I go 235, do I need to go down to 35 series?
http://www.miata.net/garage/tirecalc.html
Last edited by SRTSVTSS; Jan 14, 2010 at 10:47 AM. Reason: Automerged Doublepost
I've got the 235/40/18 Dunlops on... couldn't be happier. KILLER tire! Damn good in a straight line, and absolutely insane in the corners.
The "40" is a percentage of the width, therefore a 245/40 will have a bigger sidewall (3.9") than a 225/40 (3.5"). Here is a great java program I've used for years:
http://www.miata.net/garage/tirecalc.html
The "40" is a percentage of the width, therefore a 245/40 will have a bigger sidewall (3.9") than a 225/40 (3.5"). Here is a great java program I've used for years:
http://www.miata.net/garage/tirecalc.html
It's sort of funky the way tire sizes go you basically have
mm(metric) / %(percentage) / inches(imperial)
For a 225/40/R18 tire:
the 225 means the width of the tire is 225mm = 8.9"
the 40 means 40% of 225 is your sidewall height 90mm = 3.5"
the 18 is obviously the inside diameter of the tire in inches
for a 235/40/R18 tire:
235mm = 9.25"
40 sidewall means 94mm = 3.7"
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Joined: 07-25-08
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From: Florida
That is an awesome program, I've had it bookmarked for years aswell lol.
It's sort of funky the way tire sizes go you basically have
mm(metric) / %(percentage) / inches(imperial)
For a 225/40/R18 tire:
the 225 means the width of the tire is 225mm = 8.9"
the 40 means 40% of 225 is your sidewall height 90mm = 3.5"
the 18 is obviously the inside diameter of the tire in inches
for a 235/40/R18 tire:
235mm = 9.25"
40 sidewall means 94mm = 3.7"
It's sort of funky the way tire sizes go you basically have
mm(metric) / %(percentage) / inches(imperial)
For a 225/40/R18 tire:
the 225 means the width of the tire is 225mm = 8.9"
the 40 means 40% of 225 is your sidewall height 90mm = 3.5"
the 18 is obviously the inside diameter of the tire in inches
for a 235/40/R18 tire:
235mm = 9.25"
40 sidewall means 94mm = 3.7"
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Joined: 07-25-08
Posts: 12,450
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From: Florida
You can, but if you hit really hard bumps there is a possibility of rubbing due to the tire being wider and also 3/4" taller.
Last edited by Terminator2; Jan 14, 2010 at 12:26 PM. Reason: Automerged Doublepost