17x7 +42 with 235/40/17 - front inner clearance issues?

[blacksheep]

Ok, I am looking hard at a 17x7 wheel (4 lug, all I need). It is 17x7 +42. Nothing too crazy here, I know I will not have fender side issues with this setup.

The concern I have is inner clearance especially in the front. This wheel will be about 12mm farther inwards since the offset is close to stock and adding a wider tires such as 235/40/17, I am unsure if I will have rubbing issues.

Is anyone running such a setup or have experience. Been a while since I messed with gvr4's and wheels/tires. Any advice appreciated. Thanks!

EDIT - I don't think this matters, but I plan to lower it with AGX and H&R - Again, nothing too crazy. I know the AGX is not the greatest, but it will do. I have had this setup before and it was not horrible etc. I will only be using the car for occasional street use, so not a mega concern.

AND I don't want to do a 5 lug swap etc, I want to keep car close to stock as possible. I know lots of wheel options etc..

 

[blacksheep]

As an update I used this calculator... click

Here is what I got...Seems to check out OK, but wanted some real life experience here...

 

[iceman69510]

Having run the GSX 17 x 6.5 +46 wheel on this car for years, you need to really just consider the tire. I personally feel a 235 is too wide for a 7" wheel. Check the recommendation for wheel width for the tire sizes you are considering. You could also try measuring the distance between tire inside and the strut tube to gauge how much wider you could go.

I have used 215/45 on my car and on an Eclipse, but have also run a 225/45 on a 17 x 8 wheel on the GVR4. I feel this is more than enough tire and wheel for a fairly stock vehicle. I personally hate the tires sticking out past the fender lip, so I tend to want to optimize wheel fit on the inside to avoid this.

 

[blacksheep]

Thanks, Icee. I do see your point about 235 being too wide. I figured I wanted to maximize width on the wheel. I would go with very stiff sidewalls like the Star Specs or ZII (new version) to keep it firm.

I think 215 or 225 is a lighter tire too. I remember something about the XL rating and weight - I am fuzzy on this. But, I am unsure about the 45 sidewall, I was thinking may be 225/40/17's?

Thanks!

 

[turbowop]

I've got 235 star specs on my 8" wheels. Great tires. That would be pretty wide for a 7" though.

 

[fuel]

a 235 isn't necessarily going to provide any more grip than a 205, 215 or 225. The wider the contact patch the smaller it gets in length. You're still putting approx the same surface area of tyre onto the road whether it's a 205 or 235 wide. Not to mention a decent quality 205 will outperform a crappy 235 any day. Go for 205/45 or 215/40 on a 7" wide rim or better yet step up to an 8" rim to run 225/40 or 235/40 tyres.

 

[turbowop]

Quote:
The wider the contact patch the smaller it gets in length. You're still putting approx the same surface area of tyre onto the road whether it's a 205 or 235 wide.



I'm gonna go out on a limb here and say that you're wrong.

A wider tire puts more rubber on the road. Why do you always argue that you lose length in the contact patch? Same rolling diameter = same front-to-rear contact patch, regardless of width. Maybe if one tire is super deflated the length will grow, but that's it. So more width = more rubber = more grip.

Take two different sizes of the same tire, like a set of Dunlop Direzza star specs. I guarantee you the 235 will outperform the 205.

 

[iceman69510]

I think he is maybe referring specifically to these sizes used on a 7" wheel. It is true that too wide a tire on too narrow a wheel does sacrifice some performance because of the resulting tire profile. That is why I always suggest you stay in the recommended rim widths from the manufacturer.

 

[blacksheep]

Quoting turbowop:
Quote:
The wider the contact patch the smaller it gets in length. You're still putting approx the same surface area of tyre onto the road whether it's a 205 or 235 wide.



I'm gonna go out on a limb here and say that you're wrong.

A wider tire puts more rubber on the road. Why do you always argue that you lose length in the contact patch? Same rolling diameter = same front-to-rear contact patch, regardless of width. Maybe if one tire is super deflated the length will grow, but that's it. So more width = more rubber = more grip.

Take two different sizes of the same tire, like a set of Dunlop Direzza star specs. I guarantee you the 235 will outperform the 205.



In auto-x, which I won't be doing - Wop's theory has been proved right many a time. In stock class, people run mega-wide tires on the stock rims for this reason. Just sharing what I know. I am not an expert and a dolt in many ways...

 

[blacksheep]

Quoting iceman69510:
I think he is maybe referring specifically to these sizes used on a 7" wheel. It is true that too wide a tire on too narrow a wheel does sacrifice some performance because of the resulting tire profile. That is why I always suggest you stay in the recommended rim widths from the manufacturer.



That makes sense as well. I looked into 225's - I don't know if I should run 45's or 40's, though. I will look into this more...

 

[KiNgMaRtY]

Previous owner put 215/40/17 tires and I think they are small both ways. I am either going to go 225/45/17 or 235/40/17 when it's time to replace them.

And yes, wider does = more contact. I ran 255/40/17 on the stock 17x8 BBS wheels when I had my 2005 STi and notices much more grip from the 225/45/17 tires that came stock, and the stock tires were sticky.

 

[blacksheep]

Marty - Do you have a picture? Also, are how wide are your wheels?

 

[fuel]

tyre contact patch is determined by the force of the car being exerted on the tyre. The heavier the car, the more contact patch it is going to have (or same deal with deflating the tyres). A wider tyre isn't going to necessarily increase the total contact patch because the wider you go, the more it decreases on the other axis. This is simple physics.

I wasn't arguing that the 205 would outperform a 235 if they were both good quality - I was saying if the 235 was a horrible nasty tyre (but still wide), a decent 205 will run rings around it.

Yes a wider tyre is generally better for grip for most aspects of driving, I'm just saying don't put so much thought and stress in between the differences of a 225 to a 235 because there's always other factors which come into the equation too. One such example is winter driving where narror tyres really come into their own in snow and ice and standing water because the contact patch is narrow but long and allows the tyre to seep in deeper and make better contact with the road whereas a wider tyre can't effectively push aside snow and ice or even lots of standing water.

Here's some links which better explain what I'm trying to get at - click and click and click