Hey folks, not a car n00b and definitely not a forum n00b... so question:

Has anybody actually measured the section width of a 235/45-17 tire mounted onto a 17x7 wheel? Most of the published tire specs for just about every tire I want to use lists the 235/45 as 9.3" wide on an 8" wide wheel. I'll be mounting on a 7" wide wheel, so the assumption based on all the tire web sites' guesstimates of .2" section width change for every .5" wheel width change should put me at 8.9".

Can anyone verify that this is actually true? The proper way to measure would be to lay a tire flat on the ground, lay a straight edge all the way across, then measure from the straight edge down to the ground like this:



I know fitment isn't an issue on your Maximas, but I'm trying to shove this all into a Mazda5 where clearances are REALLY tight. Your forum was the one that had the most topics about 235/45 tires on 17x7 fitment, and none that I've found actually had real measurements.

If you've measured it before, I'd appreciate it if you let me know exactly how wide the tire is on the narrow wheel. If you're willing to help a fellow car junkie out and measure one from your car because of my question, I'd greatly appreciate it too. If you do, please list the tire manufacturer/model number with the measurement.

Thank you to anyone who can help!

 

Hopefully someone chimes in. I've only got 225's here.

Question; If you know clearance is tight, why not go with a smaller tire?

 

Thanks. I want the widest footprint I can fit onto the ground within the wheel wells. I'm running 215/50 tires already, but the Mazda5 is a pretty heavy car- especially when loaded up with 6 people plus cargo in back AND up top. The 215s are 8.9" at spec wheel width, so if I can pull the sidewalls in a hair on the 235s and still have the larger contact patch, I want it.

Plus tire selection is a LOT better and cheaper in 235/45 than in 215/50... and it looks better too. All my cars partly serve as shop promo cars since I work part time with a speed shop here in Dallas, so the more rubber I can cram in the better. Just to give you an idea of what I'm working with, here's a pic of the family hauler:



That's after a coilover install, fat rear sway bar, and camber adjusters all around. Gotta have stick and a little bit of stance!

 

I have 235/45's on a 17x7 wheel, when I get a chance I'll measure it.

 

You rock. Thank you so much!

For anyone else who's reading out there- I'd like to get a few data points. Anyone available to measure?

Thanks!

 

I'm no help for you, but I just have to say I have NEVER seen a Mazda5 I wasn't repulsed by, until your pic a few posts up.

 

Thank you! That's actually quite the compliment. It's amazing what a different wheel and larger tires will do to a car once the gap is evened out. It'll look a lot better after the side skirts (OEM) and hatch spoiler are on.

This is right after the drop but with the stock wheels and tires (205/50-17) for comparison:



Regardless of what it looks like though, it drives WAY better than anything else with 3 rows of seats and sliding doors. You can hustle this car through the twisties in ways you really shouldn't be able to. The coilovers and giant rear sway bar do help a bit, but it was pretty good in stock form too. That's why I want more tire on the ground... it's still a 3500 pound car empty, so more rubber would be nice.

 

Back from Japan.... Anyone able to measure?