Tires that run wide or narrow

[FirestormFRS]

Tire rack .com....gives you all the measurements of each and every tire they sell. Stop being lazy.

[switchlanez]

Originally Posted by FirestormFRS

Tire rack .com....gives you all the measurements of each and every tire they sell. Stop being lazy.

Says the guy who was lazy enough to overlook my references in this thread to tirerack and their published numbers.

[switchlanez]

Originally Posted by sprintertrueno86

@switchlanez I assume youre trying to do 255 18x9.5 up front??

Most likely now that I have consensus thru PM that 265 will likely rub with +45 offset. Do you think 255 will rub?

[sprintertrueno86]

Originally Posted by switchlanez

Most likely now that I have consensus thru PM that 265 will likely rub with +45 offset. Do you think 255 will rub?

No idea, I'm going staggered with 18x8.5 +35 225/40/18 and 18x9.5 +40 255/35/18.

[switchlanez]

@CSG Mike @FirestormFRS

Upon closer inspection on tirerack, I've zeroed in on two key parameters: "Section Width" and "Tread Width" (might've helped if someone emphasized these 2 specific metrics earlier). They are measured on same sized wheels so we can assume all variables (due to wheel) are ruled out for an apples to apples comparo.

I've been told the tire shoulder (not sidewall) is what rubs the inner fender line. Section width tends to be widest at where the tire meets the rim then tapers off toward the tire shoulder. That means the tread width holds greater determination on whether a wheel will rub the inner fender liner at full lock, right? According to the following specs, if a person running 245/35R18 MPSS tires on 8.5" wide wheels in front with no issues, then a person running 265/35R18 Ventus V12 tires on 9.5" wide wheels should also have no issues. Because the 245 MPSS tread on 8.5" is wider (9.2") than the 265 Ventus tread (9.1") on 9.5". If you put 245 MPSS on 9.5" wide wheels, then its tread width gets stretched even further beyond 9.2".

Ventus V12 evo 255/35R18 on 9" wide wheel: Section Width=10.2", Tread Width=8.7"
Ventus V12 evo 265/35R18 on 9.5" wide wheel: Section Width=10.7", Tread Width=9.1"

MPSS 245/35R18 on 8.5" wide wheel: Section Width=9.8", Tread Width=9.2"
MPSS 255/35R18 on 9" wide wheel: Section Width=10.2" Tread Width=9.5"
MPSS 265/35R18 on 9.5" wide wheel: Section Width=10.7" Tread Width=10.1"

[Ozzman]

Originally Posted by switchlanez

Before you dismiss my question so easily... there a vey finite number of tire sizes that maintain stock OD of our car. For 18" it would be 215/40, 225/40, 235/35, 245/35, 255/35, 265/35 and that's what we can focus on for starters and similar can be said for 17". The question of wheel variance depending on manufacturer can be ignored until we see someone put the same tire on 2 different wheel models of the same spec and prove differing fitment. I'd imagine wheel variance to be in the single digit mm range whereas tires can vary in magnitude closer to double digits since the width increments by 10mm. Have you seen the stickied wheel directory? That's a lot larger/harder to manage than the tire question.

It's not the number of possibilites that makes this impossible to manage but the lack of a metric to evaluate actual size hence my posting of this thread asking for personal experiences. Tirerack shows all evaluable dimensions for tires (like 3+ different width metrics) and for 265/35R18 the MPSS and V12 were identical across the board IIRC. There was no metric I could find indicating the V12 runs wider.

I have seen 2 Michelins of the same model and size vary as much as an inch in measured width just due to the load and speed rating being different. You will not be able to make an accurate database unless you spend a month 12 hours a day at tire racks HQ making your own measurements.