notaless

hey guys i'm running on stock 91' GXL rims, i want to know if i can run...

Tire type: Potenza's S-03
225-50-15 in the rear
and
205-50-15 in the front?

and if so, how much more of a drop would be needed for ride height to be ideal with these tires. Using racing beat suspension, with a 1 to 4 damper settings.

Cosmo_TT

iTrader: (11)

easily i have 245's on front and back with a 1.75" drop so 205 and 225's will fit

Black91n/a

How did you manage to get 245's on the front? Do they rub?

notaless: One slight correction, there was no 91 GXL, they're just the Coupe in 91, available with a couple different trim packages.

If you're tracking the car you'll want even tire sizes on both ends for better handling, if you go wider in the rear you'll get relentless understeer (no fun at all).

With the racing beat springs, they're fairly soft with not a small drop, so you may have problems with rubbing with 225's in the front. I've got 225/45/17's on 17x8's with a 30mm offset. They are approximately centered in the wheel well with very little room to spare but have never rubbed, even at the track with a stock suspension. The stock rims are 15x6 with a 40mm offset. That means that with a 225, the tire will be 10mm (~3/8") closer to the suspension, so it's more likely to rub. I've read that many people who put 225's on TII wheels have rubbing problems (also a 40mm offset). Another thing is that a 225/50/15 on a 15x6 is a bit of a stretch and the tire will be fairly bulged out, partially reducing it's contact patch. They should still provide more grip than a 205, but less than if they were on say a 7.5" wide wheel.

I'd reccomend some good 205/50/15's to be on the safe side. IMHO S-03's are a waste of money, ypu can get tires 90% as good for 50% of the price. Kumho MX's are a good tire with lots of grip and they handle the track abuse very well. They're also much less expensive. Others to consider are the Hankook RS2 Z212 and the Falken Azenis RT-615. All of those are considerably less expensive and are nearly as good.

With an RB suspension you cannot go any lower unless you cut them or heat them untill coils collapse, neither of which is a good idea. If you want to go lower, then you really need to go much stiffer, and then you'll need to invest in some alignment parts to correct the suspension geometry.

This is probably your first time out on track correct? If so then just get some descent 205's all around and go have fun. You shouldn't overthink the suspension and tires. My first time out I had a totally stock suspension and I was running on hard all season 205/60/15 Pirrelli P3000's (620 wear rating, they're super hard). The car was just fine, it handled beautifully, was well balanced, predictable and very forgiving, and I had an absolutely wonderful time. You don't need to go super fast to have fun.

notaless

I'm not really wasting that much money, since my brother is getting me the S-03's for like 75 a pop, and free installation...

WHat suspension setup do u recomend while running the 50 series tires?

Black91n/a

Wow, that's a good deal on the tires. I'd try for the 225/50/15 all around in that case, but you may need to run a small spacer up front in order to get them to clear everything. This may necessitate running longer studs in the front to accomodate the spacer, but the front studs are pretty easy to replace.

I'd say just keep the suspension the way it is now, no sense spending money needlessly. Try it out and then if you're unhappy with it, then change it. There's also no sense getting a super trick suspension if you're a novice, as you'll be the biggest thing holding the car back, not the suspension (trust me I know).

One thing you'll need is good brakes. Some good track day pads and high temp fluid should do. I've used Hawk HP+ pads and Ford DOT-3 fluid with great success, even with 2 drivers flogging the car all weekend (and I've got the single piston brakes with non-vented rear rotors). That setup works on the road too, but I wouldn't reccomend those pads for daily driving.

Make sure the rest of the car's in good running order before you go, as track days put a lot of stress on the car. Fix anything that's wrong, even if it's intermittant or only slightly wrong.

Remember, at first spend your money on track time, not mods, that'll make the car go much faster than if you spent the money on mods and still weren't able to drive it properly. It'll also make every car you'll ever drive afterwards faster. Autocross is a good place to get some practice in. It's very different, but you'll devellop skills that are useful to track driving as well.

If your dead set on upgrading, then a good starting setup is ground control coilovers on adjustable shocks (which you have already). A fairly standard starting point for the SCCA ITS club racers in 400lb/in springs in front, and 275lb/in springs in the back with the stock front bar and no rear bar. They run tires in sizes like the ones you're looking at running.

Remember, the more you tell us about you and your situation, the better the advice can be.

Turbo23

iTrader: (4)

245s on stock wheels? If that is so, which is highly unlikely, talk about looking like a tractor. 225s are the max for stock wheels, unless you want the side walls to bulg out. If your NA 205s are fine, just make sure you get a good set of tires. Espically if you want to be competitive. Perhaps yokohama a032rs. or some hooisers. And make sure your tire pressure is set right, that can drastically change how your car will feel

Black91n/a

He's right about the pressure thing, and 225 is the max for stock wheels, but unless it's competetive racing, then don't run race tires. Running street tires keeps the cost lower, and you'll learn more about how the car will handle out on the street. I'm assumung you're just talking about a track school correct? If that's the case good street tires are the way to go untill you get really good and really serious about it. 205's are perfectly adaquate, but 225's will give more traction, and if there's an option of one, then you may as well try it.

trainwreck517

iTrader: (1)

Just use 205's with good rubber, for my track wheels I have stock vert BBS wheels with aziens on them and they stick like glue.

Cosmo_TT

iTrader: (11)

lol yeah highly unlikely
its so funny when people come on here and think they know it all like saying that what tires are on my car and have had the same size tires on them for 7 years is "highly unlikely"
yes they are on stock 10AE rims and DO NOT RUB and do not look like tractor tires
by the way 225 and 245 is width of tread tractor tires have tall sidewalls so if i said i had 245/85/16 then that would be crazy and like a tractor i run 245/45/16 and have for 7 years
i am not saying this is the best or not i am just saying what i run and how they fit (period)

rrw

iTrader: (2)

yeah i bought some mustang gt bullet wheels and the tires on those are 245 45 17. i cant wait to get my motor in to see if they fit right in the front. they may be rubbing the shock tower just a tad but they spin freely when jacked up but with no room for finger between tire and spring. i think they look sick i just hope they fit.

Sideways7

iTrader: (7)

Got any pics?
I personally run 225 width tires with maybe an inch drop and have no problems at all.

Black91n/a

That's a little different. TII wheels are 7" wide. You'd have a lot more trouble getting a 245 on the wheels in question, as they're 15x6.

Cosmo_TT

iTrader: (11)

i will try to take some and post them on here

Turbo23

iTrader: (4)

you will be the first person on here to fit 245s on any stock FC wheel, and not have massive rubbing problems, and bulging. i ran 225s and rubbed in the front

90WhiteVrt

get 225's front and rear on some vert rims and you'll be golden!