Performance vs Looks Tire Question

[nightfire]

So I have a bit of a dilemma and not enough knowledge on the matter to solve it. It's time to upgrade my wheels and tires and I want something that looks good but doesn't in any way compromise the BRZ's great handling and feel. I'm looking to upgrade the grip but I don't want any sketchy tendencies out of the tires at the limit. I know 17's would be more ideal but the wheels I want only come in 18's.

So my question is at what point does the tire aspect ratio influence the overall grip and "feel" of the car at the limit? The tires that would fit the wheels I am looking at would be 225/40/18 front and 255/35/18 rear staggered or either one of those dimensions all the way around (more on that later). However, I am looking into running a much sticker tire with them - Michelin Pilot Super Sport's. Would these tires decrease the usable sidewall flex and therefore feel sketchier at the limit due to the new aspect ratio?

Also, as previously mentioned, would you guys recommend the staggered set-up or should I just run either the 18x8.5 or 18x9.5 on all four tires to get a better feel out of the car?

Thanks!

[Vracer111]

Not sure how you drive, but with my daily driving habits I have worn down the rear tires twice as fast as the fronts (with no drifting or burnouts ever done in my FRS) on my sticky Extreme Performance set. Would be annoying to me if I had a staggered setup and couldn't rotate the tires to evenly wear down a complete set of tires...

Tire compound/construction and wheel width has more effect on vehicle feel and handling than tire size. I kept the stock 215/45-17 tire size but with Kumho Ecsta XS tires and mounted them on lightweight 17x8 +36mm offset Kosei K4R wheels and it really changed how the car behaved...I actually grew to not like it on the street, you had to push it too hard and too far to have any fun comparable to the stock setup. Wider track + major increase in grip just reduced the daily driver fun of the car. The wheel/tire combo was excellent on an open track day though...being 4+ lbs lighter than stock really increased the ride quality and the tires gave very neutral and progressive handling characteristics with plenty of grip while going at it on track.

Going to the stock tires but on lighter and wider wheels (Enkei Fujins 17x7.5 +40mm offset) for the daily driver set gave better ride quality more responsiveness than with the stock wheels. A little more fun to daily drive as well when compared to completely stock.

[TRD8]

Definately would recommend same size all around for rotation. And also, changing rims/tires definately changes ride and handling. So if you don't want to change how your car feels, make sure the final dimensions of the tire/wheel assembly are the same.

I would keep 215mm tread width stock, I love how these things handle and although haven't experimented yet, I know upgrading to a wider tire will make it feel less light on its feet.

[wparsons]

Forget about rotation, if you don't want to screw up the balance don't run staggered wheels/tires. Going wider out back will just make the car push.

I'm not sure what you mean by sketchier at the limit, but a smaller sidewall will make the tire translate more feel back to the steering wheel and it will also react more directly (quickly) to steering inputs.

If you're relying on a soft sidewall for traction over bumps then your suspension isn't doing its job.

[nightfire]

All good points, thanks for the info everybody! I'll probably end up going non-staggered 18's

[f0rge]

I have 225 and 245 PSS's on 18's on my car and its WAY better than stock, forget about ruining the handling, it got significantly better.

PSS are great tires, you can definitely feel when the car is losing grip and no crazy snap oversteer or anything. If you're that concerned about the feel of the tire at the limit, read some tire reviews from Car and Driver and other sources that directly compare how the tires act at the limit.

Full disclosure I'm also lowered on eibach sportlines.

[nightfire]

That makes me feel a lot better I think I'll pull the trigger on the decision soon

[Gunman]

Originally Posted by wparsons

If you're relying on a soft sidewall for traction over bumps then your suspension isn't doing its job.

Yes. The only compliance you want in the system, in an ideal world, are the springs and dampers.

[nightfire]

Well with flexing sidewalls it wasn't so much for traction over bumps as it was for the increased forgiving nature at the limit. The bumps are a separate issue of potentially bending the wheels because of all the extreme potholes in NJ. My friend had stock 18's on him GTI and bent those even while avoiding all potholes. Stock wheels are usually stronger than cheaper aftermarket ones I would think.

[wparsons]

Less sidewall stiffness automatically doesn't make them more forgiving at the limit, that's down to compound and tread pattern more, alignment can also play a factor.