Hey Guys,

Ideally I wanted to get some Gram Lights 57DR wheels in an 18x9.5 +22 configuration, but they're not in-stock anywhere in the US. AS a result, I'm looking at the following two options and need to know which setup will require less work rolling/pulling fenders, etc... (whatever it takes to fit!)

18x9.5 +12 with a 265/40-18 Bridgestone RE-11 Tire
OR
18x10.5 +22 with a 275/35-18 Bridgestone RE-11 Tire
OR
18x10.5 +22 with a 285/30-18 Bridgestone RE-11 Tire

Thanks in advance!

 

18x10.5 with a really low offset with 275-285 tires.

 

265/40 will be the most work, that's a really tall tire compared to stock.

The other two options are pretty similar, although they'll all require work.

Do you have a wheel emergency, or could you wait on the best option (9.5+22) to come in?

 

More of a tire emergency. But tires will somewhat dictate the wheel size.

 

1st what is this going to be used for?

I would not run 265/40. Read through this thread for reasons why: https://www.evolutionm.net/forums/ev...apability.html

275/35 is closer in overall diameter to stock then a 285/30. So I would go with the 275/35 over 285/30. They'll both give you issues with clearance, and require a roll/pull in the back.

IMO when modding these cars patience is important. If this isn't for an auto-x build I would highly recommend waiting to run an 18x9.5+22 with 265/35 tire. There are plenty of other tire choices besides the RE-11 if you can't find those in your desired size. i wouldn't get an 18x10.5 wheel because it'll hurt performance more then help for anything besides auto-x.

 

No planned autox. .. just a street car. The tires are part of the issue, but the real problem is that I cant get the wheels I really want in 18x9.5+22 for like 3 months.... none in the US1

 

I'd wait 3 months to get the right part. I'd also pm every vendor on here, usually with enough digging and google searching you can find what you are looking for with wheels in my experience.

I have a hard time recommending an 18x10.5 wheel as it will impact and hurt performance unnecessarily.

 

ON what information do you base your claim of 10.5 hindering performance?

 

how much more is the steering wheel with 275 or 285?

 

simply the added weight.

Personal experience, experience of others, seeing what people settle on at the track.

There's the guy kick *** at yas marina and he's only running a 255 tire... That cars making upwards of 500whp. So if you're at stock power or basic bolt-on power, an 18x10.5 is just too much imo.

And I say this owning a set of TE37SL's in 18x10.5....

 

everyone noteworthy driving an evo x in time attack i've seen on radials uses a 10.5 inch rim with a 275 or 285 tire. Slight stretch, less tire carcass deflection, higher ultimate grip, more predictable.

 

Well here's a "noteworthy" one who doesn't:

EVO X sets unlimited class record at Yas Marina

And there are many others. There are arguments both ways, I just think it's excessive if you are using it for street driving and weekend warrior on a vehicle without stiff suspension to take advantage of the added contact patch and proper race camber settings.

Even then the added weight probably hurts you more then the slight additional grip until you get to higher power levels.

 

Keyword, radials. That guy is on bias ply slicks.

But this brings up a really interesting thing i've always wondered that in no way has anything to do with this thread. Everyone running rcomp slicks has a 9.5 inch rim, while everyone noteworthy on street tires runs 10.5 inch rim. Why not just stick with 10.5 and put a fatter hoosier on? Do they not make low-pro hoosiers? Is fitment that impossible with wider R comps??

long story short, extra weight of a 10.5 inch rim hindering ultimate track performance holds no water. This issue seems to be driven more by tire selection than anything.

 

Ok fine. The weight isn't the rim, it's the tire choice. but a stretched tire doesn't improve performance.

The larger the tire, the more weight (generally speaking...). When i mounted 275/35 star specs on my 18x10.5 te37sl's I could clearly feel a performance (acceleration loss) despite the fact that the total weight of the wheel/tire combo was less then the stock wheels with 245/40 tires.

the reason being that my "upgrade" moved the weight distribution further from the center of rotation and clearly increased its moment of inertia. So despite the entire combo weighing less, it still takes more energy to accelerate it to whatever angular velocity.

of course, with a 265/35 tire you have less weight in the tire (normally...) and not as much of a performance hit. But being it's slightly smaller diameter you are changing the final gearing making it a bit shorter and gaining acceleration that way as well, except you have to shift sooner...

The reason to not run 10.5's with r-comps is simply you don't need it and even though the weight isn't much difference, it's still usually an added pound in the worst place possible. Oh, and stretched tires are not a good thing...

 

I think you'd find most people that race on street tires would disagree with you. Everything I've seen that models actual tread and road interaction suggests that grip has no dependency on load assuming isothermal conditions and ignoring carcasss effects.

Two hypotheses for load sensitivity assuming area change are: thermal effects reducing grip of the compound and carcass deflection causing the tread slip angle to be different to the wheel's slip angle (Trevorrow 2006 Monash University Phd thesis)

Wider tires are better in both these cases, they have higher in plane belt stiffness (less carcass twist) and the tire is not being heated as much because it is in contact with the road for less time and cooling for longer due to the shorter patch. The one variable here that we can control is carcass twist, which is a byproduct of stretching tires.

My origional question still remains. Hoosier makes much wider tires than 285. So why stick to 285's on 9.5 rims?? Why not move up to 315's or 305's on 10.5?? Do you mean to tell me an Evo will be slower on 315's vs 285's because of the extra weight? I sincerely hope not.

Now if you wan't to bring the discussion back to radials with a square profile vs the same size radial stretched, please tell me how a stretched tire with less carcass deflection creates less traction.

Or if your argument is still that 3 extra pounds from a wider rim will make you slower, please tell me how power trumps ultimate traction?