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964 widebody tire question

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Old 10-08-2007, 03:56 PM
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chancecasey
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Default 964 widebody tire question

I know this has been beaten to death, but I want to do something that seems very much on the edge of what is / is not possible.

There are spec tires I must use - 10.5/13 inch wide front/rear, which comes out to 267/330 mm, respectively. They are bias-ply slicks.

I have a narrow-body C2 that I WAS putting 11/14" RSR fenders and quarters on, which would have fit fine. I got the RSR parts for very cheap, but I'm not convinced I really like them, and now have the opportunity to get a 964 widebody kit for relatively cheap. I will be getting wheels made so offset isn't really a concern.

Any opinions on whether I can stuff that kind of tire under the widebody body, without modifying the flares?

Last edited by chancecasey; 10-08-2007 at 04:13 PM.
Old 10-08-2007, 06:00 PM
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garrett376
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Hmm, on my widebody race car I have 275 Toyo RA1 rears on the original 9x17" wheel - adding 4" I do not think would fit without cutting. It would not fit on my car at least!
Old 10-08-2007, 09:19 PM
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race911
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Well 275/315 combos work fine on 930's from the dawn of time, but you run into two issues with inner fender rub that will blister the paint. The car has to be pretty stiff, or it has to sit fairly high. That's with a 17" radial. No experience with the Goodyear race tires and their sidewalls.
Old 10-08-2007, 09:55 PM
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ronone10
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What body kit are you getting?
Old 10-09-2007, 12:25 AM
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BlackWidow964
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315/30ZR18 Hoosiers fit under my RSA with a wide body kit just fine.
Old 10-09-2007, 01:20 AM
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JW in Texas
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I'm running 315s on 11.5" wheels no problem.
Old 10-09-2007, 01:43 AM
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garrett376
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Originally Posted by JW in Texas
I'm running 315s on 11.5" wheels no problem.
Do you think his 13" wheel would fit? 2.5" greater width is a lot!!!

Nice to hear you guys can cram that much tire width on stock widebodies - time for some fatter rubber!!!
Old 10-09-2007, 01:54 AM
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chancecasey
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Yeah, I have no experience with the Goodyear slicks either. The rears are very close to the "normal" outer diameter, the fronts are significantly smaller diameter. The actual widths could be who knows what compared to other mfr's actual mounted width vs. advertised width. Only way to know would be to take an actual tire and stick it under a turbo 1/4 and see, but I have neither available right now.

The rear wheels would be only 12" - it's the tire that's 13"

A guy on pelican is selling the kit - from Patritti - who doesn't even make them anymore. $1200 - all fiberglass - both bumpers, fenders, quarters, rockers. Good deal - somebody should jump on it. I almost did but, crap, what a PITA it would be to have to turn around and sell them. Sounds like it would be, at BEST, an extremely close fit, but too risky for me especially since I already have parts that will work and other things I need to buy - roll cage, monoballs, harness/nets/HANS etc etc etc man will this thing EVER be done???
Old 10-09-2007, 02:28 AM
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race911
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This for the GTL class? The $$$ on suspension development are going to dwarf everything else.
Old 10-09-2007, 02:33 AM
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JW in Texas
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I just went out & took a quick look. My tires are 12" wide & I still have about 1.5" of room to the inside so I think you might be able to make it work. Your offsets will need to be nuts on though.
Old 10-09-2007, 03:58 AM
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chancecasey
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REALLY? Wow. That is awfully close, though, definitely within the range of problems if the tires are indeed a 1/2 inch wider once mounted and on the car. Sure would be nice to have the better aero of the C2 turbo than the 11/14 RSR flares, though.

Yes, it's GTL, and yes, suspension is the bear. Replacing the "bushing-train" alone will be my biggest expense. I will leave one set of rubber intact, though, the rear shock mounts - as they don't seem to do much in terms of the geometry. I'm also going cheap on the struts and just getting my barely-used Bilstein HD's revalved. It's definitely going to be one of the cheapest cars out there of any class - hopefully I can make it up with driving
Old 10-09-2007, 06:25 AM
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Geoffrey
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I have a 12" wheel under my stock C2 Turbo body rear quarters. If you are talking about the 993 style RSR fiberglass body that was used on those cars in the IMSA days, made by I think Patritti, then they ran 13" wide wheels with 310/710/18 slicks. You should be able to look up the tire dimensions and compare to the Goodyears. Also, the Champion #72 964 Turbo LM ran the same rear wheel/tire combination with the 964 trailing arm.
Old 10-09-2007, 12:24 PM
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chancecasey
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No, they actually used to make a C2 Turbo kit and that is what this is. The guy verified the size by comparing the 1/4 panel to a 965 in the shop and said they were identical.

I have no idea how to look up what you are talking about. I guess, I could drive out to see Tom's tires on his car and try to measure them. Geoffrey, do you know how much extra room you have, and what your mounted tire comes out to, width-wise?

Last edited by chancecasey; 10-09-2007 at 12:55 PM.
Old 10-09-2007, 12:42 PM
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Geoffrey
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I have no extra room at all.

You can find tire widths at any of the tire suppliers website. www.sascosports.com, www.bobwoodmantires.com, and www.jdmotorsports.com

I run Michelin 27/68/18
Old 10-09-2007, 01:01 PM
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chancecasey
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They all say section width is 13.7 - sounds like they'd be too wide. Right?


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