Negative effects of using a wider tire than wheel

[jakelandry]

Those not interested in having their time wasted can skip to the bold part of the thread.

I recently pulled my wheels off to do some light suspension work to find this.

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So new tires are in order. Because I am in my senior year of college i'm fairly broke right now so the budget is pretty tight. Ive recently shifted my interest more from drag racing to road racing and autocrossing. Not necessarily on a competitive level or anything, just obtained interest in suspension and handling related aspects of our cars. Originally I wanted a set of hankook r-s3's but with my budget I moved down to federal 595 rs-r's and the nankang ns-2r. Apparently it is nearly impossible to find a set of federal's in the 2 sizes I want so that leaves me basically with the nankangs.

The tires are going on a set of 18x8.5 gramlight 57f's. The appropriate size would be a 235/40/18 but i'm considering a 255/35/18. I currently have nitto neo gen's in a 225/40/18 stretched (from previous owner) and I don't particularly care for them or the stretch as I prefer the tire to overlap the rim slightly for protection, looks, and a wider contact patch. Ive had a very hard time getting enough traction in first at the drag strip to get a 10 seconds pass and I know the wider tire will help with that, but before I bite the bullet I wanted to know if having the tire overlap the rim would have significant negative effects on handling. Below is a picture of a 255/35 on a 8.5 wheel for reference.

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[estoyaqui30]

That looks normal and correct. I'm running Dunlop Sport Maxx 245/40-17 on 17x8 rims (evo ix) absolutely no problems. I wold say, just make sure the tire is not rubbing especially on the back, where it would destroy the sidewall.

 

[jakelandry]

Thanks for the reply. My previous tires were ruined from toe not rubbing or anything to that nature. I just diddnt know to what extent you can put a wider tire on a narrow rim before performance is compromised.

 

[2gmitsueclipse]

I run two sizes for pavement at stock ride height. Both 235/45/17 and 245/40/17 of 17 x 8 +38 rims. The 235/45 fit comfortably and are what are used for street duty. For track days and autocross, I run 245/40 on the identical rim. The 245/40 needed a slight roll is the rear as they would contact the edge of the tire on hard turns or when the suspension squatted. You would have no problems with a 255 on an 8.5 rim, just consider your offset and ride height. I would move up to a 255, but am limited to 245 for classing reasons. Ideally, you would want at least two sets of tires if your interested in auto cross/track days. A tire designed for grip will have wear much quicker due to the compound of the tire. A tire with better wear will be better on the street (for your wallet). Don't be afraid to go with used tires so long as you are careful with your purchase. Learn how to read date codes to see the age of a tire (big deal for performance tires) and the type of person to buy from. Being AWD, you will want to be careful not to buy tires with uneven wear IE: RWD, FWD.

Here is a helpful tool for tire sizing:

http://www.tyresizecalculator.com/tyre-wheel-calculators/wheel-rim-size-calculator

 

[TSiAWD666]

255/35 on 8.5 is a good fit, but only for the wheel. It is very difficult to fit that under oem fenders without a huge amount of camber. Huge as in detrimental to handling. It took fender flares before they fit for me, otherwise they would rub quite a bit in the front on full compression, and in the rear I think I had like -2 deg camber to fit with the lip rolled upwards. It's just too big a tire unless you're ready to modify your body panels.

 

[jakelandry]

255/35 on 8.5 is a good fit, but only for the wheel. It is very difficult to fit that under oem fenders without a huge amount of camber. Huge as in detrimental to handling. It took fender flares before they fit for me, otherwise they would rub quite a bit in the front on full compression, and in the rear I think I had like -2 deg camber to fit with the lip rolled upwards. It's just too big a tire unless you're ready to modify your body panels.

I knew it would take significant camber to fit them in the front to clear the fenders however it is nice to hear from someone who has actually fitted a set and tested everything. Did you try just slotting the fenders before moving to flares? While im not against going flares, I'm not ready to take my car to that level just yet being in school and whatnot. I suppose 235's would be more appropriate given my circumstances. Feel free to further discuss the topic however as I am always willing to learn.

 

[snowborder714]

@turbosax2 is running 255's all around on 17x9" wheels with no flares. Suspension is DG Koni setup with 700# or 800# front springs. The front shocks also have a bit of bump stop spacer on them to try and keep the SPC upper arms out of the shock tower, but they will definitely hit before the tire hits the fender. One of the rear tires has slightly come in contact with its fender, but only minor. None of the fenders are rolled yet.

 

[TSiAWD666]

Changing the compression range of the shock completely changes the discussion. I guess that's an option but I think it's cutting one corner for another.

 

[jakelandry]

I know jaxness also runs 255/40's on 17's which is the exact same height as a 255/35/18. What was the wheel and tire you tried on yours @TSiAWD666 ? I'm not questioning your testing or anything, just curious. I'm only on tokico's right now which are garbage and I have no camber adjustability in the front at all. I'm not exactly trying to track the car right now, Ive just literally never pushed my car unless it was in a straight line and I'd like to get a feel for cornering a little more. I'm not necessarily dead set on a 255, I would just like the wheel protection, extra contact patch (for drag), and I prefer the look of a meatier tire.

 

[TSiAWD666]

That's a good question, and any testimony on this requires numbers on wheel specs including offset and camber adjustment, and even to a small degree the exact tire used since dimensions vary despite the spec.

I was using Kumho Ecsta Supra 712 tires in 255/35/18 on 18x8.5" with a 35mm offset, running I think -1.5 deg camber up front with no fender modification, and -2-ish in the rear with the lip bent vertically (or really close to it). The fronts would rub when I bottom'd out, and the rear if I recall correctly just barely cleared.

In the end if you can take the negatives without concern and really want the 255, then go for it. I'd just find a smaller tire and stop trying to fit something that in your type of driving is gaining you nothing but complication.

I should add that going to such a tire it's going to stick out from the fenders. To some this looks like ass, others it looks good. Either way it's adding a good amount of drag to the car with the tire being exposed to airflow. Would you notice it from how you described your driving goals? Nah.

 

[Black95TSIawd]

I ran 255/35/18's on 18x9 +35 wheels and had no rubbing issues. This was with 800lb front and 350lb rears and about a 1.5 inch drop. However, i have yet to track test, only aggressive street driving which may not be enough to push to contact.

 

[psycho]

I'm running a 255/35/18 Yokohama S-Drive on Evo X 18x8.5 +38 on a 500# front spring and im pretty low on "stock" camber. To not rub, I had a local fender roller not only roll the fender but also push the fender just slightly out giving a bit more room. The tire just barely misses the fender without contact.

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[Dyesuperman]

You will have no issues with the 255s, just rolling of the fenders. I ran 265s with pulled fenders before deciding to go widebody...you would be amazed at what you can fit if you get creative

 

[ceedawg]

Will.I have an issue with using 245 45 17s on rpf1 17x8.5 40 offset?

 

[snowborder714]

I don't know if they'll clear the rear knuckle. I've posted clearance specs somewhere on here so you might want to search for those.

 

[ceedawg]

I don't know if they'll clear the rear knuckle. I've posted clearance specs somewhere on here so you might want to search for those.

The fronts fit ok but the rears need spacers. I'm thinking my issue is that the profiles on these are 45s and what I really need are 40s. worried that even though the rear will clear with spacers what's gonna happen when I start road racing. Are they gonna rub with this 45 profile?

These tires and rims originally came off of a 3000 gt vr4 TT. Hope I don't have to ditch these RE01s because of the 45 profile.

Brian I saved your hood scoop DIY so now I have got to look for your tire recommendations. Looking now thanks!

 

[Black95TSIawd]

I ran 255/35/18's on 18x9 +35 wheels and had no rubbing issues. This was with 800lb front and 350lb rears and about a 1.5 inch drop. However, i have yet to track test, only aggressive street driving which may not be enough to push to contact.

So I started autocrossing this year and yes, i experienced major rubbing. I raised the car a quarter inch, set my front camber to -2.7 front/-1.6 rear, and rolled my rear fenders and still rub a bit in the back. The fronts just barely skim the front fender under compression. I'm going to set the rears to -2 camber and try to roll them a little more aggressively. I'm hoping this takes care of it. Also, switching down to 17x9 wheels and 245/40 RE71r's. I dont think an extra wide 255 autocross tire will fit in the back without some serious spring rate/high compression shocks.