255/35/18 vs 285/30/18 all around on 300whp FD Rx7
 

Hey rx7s owners I have a 1994 rx7 and I just bought a set of rpf1s 18x9.5 +45 on all corners with this wheel size I can run all the way up to a 285/30/18 all around without having to mess with the front or rear fenders. I'm lowered on tein coilovers with edfc. I know my tire diameter should be 25 inches so I'm deciding to run between 255/35/18 that measure at 25in or 285/30/18 that measure 24.7.

So my real question is should I run cheap 285/30/18 Sumitomo tires that cost $126.00 each tire or should I run 255/35/18 Bridgestone potenza s-04 tires that cost $179.00.

I daily drive my fd and go to the GMR canyon twice a month so what tire should I go with for more grip, a wider tire like the sumitomos or the less wider stickier tire Bridgestone potenza 180 is the most I'll spend on each tire.

For your wheel size and what you want to do with the car, run the 255 Bridgestone tires. I personally have had Sumitomo tires and, in my experience, they had lousy grip and wear characteristics. I know you "can" run 285 tires on that rim size, but the best overall feel you will get is if you run a tire that the same width as the wheel. 9.5" wheels with 255 section tires will provide the best response.

Cheaping out on tires is not a good move either. You don't get all dressed for the club and walk in wearing Crocs. Tires are your link to the road, and the better grip you have laterally and in acceleration will translate into better braking as well. I'll link a fantastic article about choosing the right tire size for spirited driving.

How to PROPERLY select and size TIRES for PERFORMANCE > MotoIQ - Automotive Tech, Project Cars, Performance & Motorsports

^ good article, thanks for sharing.

I agree.

You aren't on the clock racing so why put the wider tires on that will possibly have more grip at the expense of steering response and feel.

On the street you are more likely to be able to drive confidently on 255 tire on 9.5" wide wheel because you can tell what the hell is going on at the contact patch.

If you do want more grip (without the expense of response and feel) choosing a decent tire is the best way to get it. I wouldn't put those S-04s on my Mazda3 daily let alone an FD daily.

I daily my Mazda3 with Federal 595RS-R 140utqg.
Those are $128 in 255/35-18 and will outperform anything but the best max performance summer tires.

OK thanks everyone I'll see what I decide to go with and yes I saw that the federals 595rsr and 128 but they're r compound and they might take a while to warm up and plus I feel the 140 thread will wear out fast

The RS-R are most certainly not R compound tires and compared to other max performance summer tires the RS-R work well in lower temps.

I had gen 1 Hankook RS-3 and those tires tried to kill you in the cold. They were worse in the cold then the DOT-R race tires I favor (RA-1, R888, NT01, TD, RC-1).

RS-R will grease out at very high temps/hard use (part of why they are popular for drifting).
They are much like the Toyo R1R but with a chunky tread pattern so they don't fall apart easily. Like better, cheaper Falken RT-615Ks really.

I live at the very top of California and lately I have been driving home in 36-38deg F on my RS-Rs and they have very good grip still.
On my FWD Mazda3 in 205mm they are great in the rain, on my FD in 265mm they weren't so great in the rain as it hydroplaned fairly easily once the tread wore down.

The RS-R do wear out fairly fast compared to a harder tire if you are just driving gently, but they stand up very well to racing (where harder tires wear very fast).

I got ~25,000 miles out of RS-Rs on the FD including auto-x racing 2x a month. But I ran them down to nothing. Probably 15-20,000 miles of legal tread depth.

RS-R should last about a year and half and 20,000 miles if you don't race (just daily and canyons).

Ideally you should replace any tires every year as the oils evaporate and they just aren't as good after a year.

how do the RS-R compare to zii?

They are pretty similar in performance, but even the Dunlop ZII is a more refined tire.

Yokohama AD08R is another pretty similar tire, but more refined again than the Dunlop.

RS-R are quite loud on the street and have lower production tolerances. RS-R need lot of weights to balance when new, less when worn down. They have a spliced tread that separates and looks like a gash (but I have never heard of one separating and they are huge in drifting).

But hey, RS-R are $138 for a 285/30-18 and they are fast!

If budget is not a concern I like the Bridgestone RE-71R for a street tire, but they cost more and wear out super fast (they are very much like a DOT-R)

http://www.tirerack.com/tires/tests/...y.jsp?ttid=202

I have the Federals on my Dodge SRT-4 and holy crap, they are loud. In my sedan, they sound like a bad wheel bearing. I can't imagine what they would be like in a hatch, but they are cheap and crazy grippy. I feel very confident with them in all but heavy standing water and snow. Like BLUE TII said above, they do take a bunch of weight to even out. I got mine second hand because the PO couldn't handle the noise. They also had Les Schwab sipe them, which I wasn't happy about, but free tires to me.

Since it seems like price is an issue and you want the best grip for the dollar, the Federals are very tough to beat. I don't track my SRT, or auto-x it, so I couldn't respond on their grip at the limit, but they do feel good in the dry when getting onto an on-ramp.

I have 18 x 10 +50's all around, with 255/35 in the front and 285/30 in the rear.

The 255's just fit better in the front, so I would vote for those all around (I tried...). Less following of road imperfections with the 255 tire as well, so easier for street driving.

And, I'd like to add to the suggestions saying a better tire in the smaller size will be more rewarding overall. Don't cheap out on tires - the rubber meeting the road may just be the most important interface on the car!

Nice wheel size for the car!

PREACH, BROTHA, PREACH!!!

As good as wide tires can look, there is a point where you will not get the benefit of the wider rubber, especially in turns and transient response. The worst thing you want is for your car to feel dull and heavy, especially in turns. 255s are plenty wide for a square fitment on stock and mostly stock suspension. I know there are others that have gone way wider, but I know in my experience that a narrower tire has better feel and less "push" or under steer in corners.