Tire size recommendations

esonu

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Just pulled the trigger on some welds 18f/17r and was wondering what rear tire size do people recommend on a 10inch wheel. I have 18x10s in the rear right now with 315/35 but it has slight rubbing issues. Would it be worth it to go 315/35 on 17s or better off 305/35. Just looking for opinions. Tire itself will more than likely be r888r.
 

shurur

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I had 285 on the rear ...at most..

I think anything past 295 rear will need the fenders rolled.
just my .02.
 

TerminatoRS

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I'm with him^. Go with 295's, maybe even 285's on a 10" wide wheel. R888R's in a 315 on a 10" will leave a lot of sidewall bulge. I'm guessing the rubbing is on the insides based on the 10" width + 315 TQ combo you've got now. 315's are a little wide for that wheel so I'd bet the sidewall bulge is the main reason it rubs at all. I've got the same tires on 18x10.5's and they're a perfect fit without any rubbing unless I unload the rear suspension.
 

01yellercobra

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I had 285 on the rear ...at most..

I think anything past 295 rear will need the fenders rolled.
just my .02.
Would that be an 18" rim thing? I only ask because my car came with 315/17's and nothing rubbed. But when I switched to the nittos and FR500's I had to roll the fenders.
 

TerminatoRS

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I think it's very hit and miss when it comes to this subject. It seems to vary by vehicle and how far off center the rear end is. Obviously suspension changes play a factor as well. It's a little surprising to me that you had to roll the fenders for Nittos (I thought they ran narrow) and FR500's (aren't they 10" wide and not 10.5"?).

For instance, I run 18x10.5's, Toyo TQ's 315/35, H&R Race springs with the stock isolators, and all I had to do were the low profile IRS bolts. No fender rolling and they only rub on the IRS when I lift the rear of the car up. I've run 315/30 R888's the same way without issues. Ran Nitto 315/35?/17's years ago also without issues.

Other folks have gotten away with 18x11's and 335's with just low pro bolts and/or a small spacer on one or both sides. Maybe extended wheels studs too. Meanwhile some people seem to need spacers for 315's. No rhyme or reason. Just a case by case situation as far as I can tell.
 

01yellercobra

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The 17" FR500's are 10.5" wide. The 18's are 10" wide. I don't know why they did it that way.

It's definitely subjective to the entire set up. My 04 came with 17x10.5" Cobra reps with Sumitomo tires. It didn't rub at all. Put on my FR500's with the Nitto 555R's and it rubbed the fenders. The same set up rubbed on my 01 as well. So I had to roll the fenders on both cars. I also discovered the IRS in my 04 is set to the passenger side. So I have to run a 1/4" spacer on the driver side to even things out.

The old school Nittos run narrow. The G2 series runs wide.
 

TerminatoRS

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Ahhhh...I didn't know the widths varies from 17 to 18. Odd they did it that way. Maybe they allot so much material per wheel. Added diameter for the 18's took material away from the width. lol

Certainly all vehicle dependent then as you're another example. I guess I just got lucky!

I'm interested in trying the new Nittos next season. I've made TQ's last 3 seasons so that should give you an idea how I drive the car. ha
 

01yellercobra

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I might be trying the new Nitto drag radials soon as well. I had mine off last weekend and noticed they were down to the wear bars. Oops.
 

shurur

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Mine are 17x10.5.
I am not sure what the rim size was on the cars I saw and folks I talk to though.

Would that be an 18" rim thing? I only ask because my car came with 315/17's and nothing rubbed. But when I switched to the nittos and FR500's I had to roll the fenders.
 

shurur

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I think it's very hit and miss when it comes to this subject. It seems to vary by vehicle and how far off center the rear end is. Obviously suspension changes play a factor as well. It's a little surprising to me that you had to roll the fenders for Nittos (I thought they ran narrow) and FR500's (aren't they 10" wide and not 10.5"?).

For instance, I run 18x10.5's, Toyo TQ's 315/35, H&R Race springs with the stock isolators, and all I had to do were the low profile IRS bolts. No fender rolling and they only rub on the IRS when I lift the rear of the car up. I've run 315/30 R888's the same way without issues. Ran Nitto 315/35?/17's years ago also without issues.

Other folks have gotten away with 18x11's and 335's with just low pro bolts and/or a small spacer on one or both sides. Maybe extended wheels studs too. Meanwhile some people seem to need spacers for 315's. No rhyme or reason. Just a case by case situation as far as I can tell.

I think it is that 17 has more sidewall and may have a higher chance of rubbing or..vise versa.. not really sure. Also some of my samples may have been SRA folks..i.e. Mach 1 guys...so that is my general disclaimer.
 

esonu

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The current rubbing issue I have is actually the fenders hit. But it’s only on deep potholes. So it is on a rare occasion. It doesn’t seem like r888r comes in a 295 either. Might have to change the tire selection also. My irs seems to sit pretty even on both sides so I don’t have that issue. Maybe I should just wait till the wheels come in and maybe mount them on the car and see how much clearance I have under some load.
 

tv’s 03

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I couldn’t figure out what wheels I wanted. So I ended up saving myself money and bought the SVE Deep Dish 03 Cobra replicas to match my stock wheels. I got the 17 x 10.5 and put MT ET Streets 315” 35 17 on them. I do have MM low profile rounded IRS bolts. No rubbing. I’m happy
 

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