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Wheels and TiresNeed help with wheels or tires? Got fitment issues? Have questions about tire performance and handling? Ask all of those questions here!
That is just one of the issues with 3rd gen wheels on the market (well, most of them anyway). You obviously have a lot of clearance with your wheels, but other wheels (like the Hawk's 17" wheels) are very limited in brake clearance on both the spokes and wheel barrel.
Originally Posted by TC3G89
wheel spacers allow change in backspacing but the offset will remain. the offset is made into the wheel design. for example, with my vette wheels are a +56mm offset which equates to 7.5" backspacing on a 9.5" wide wheel. my 1.625" spacer takes up the backspacing but since the offset is unchanged, there is now an additional 1.625" gap between my wheel and caliper, which i do not like. at all. but it is what it is. if you were to have a wheel that is 9.5" wide with only a +15mm offset, the backspacing would be the same as what i needed with no spacer required AND more likely than not the design of the wheel would allow the spokes to stay closer to the brakes, giving the wheel either 1) a more "concave" look or 2) a lip at the outer edge of the wheel.
the measurements you are going to use, IF i am correct, would set your rear tires roughly a 1/4" outward more than mine and the fronts about 1/2" out more +/- 1/8" or so
17-inch: 17x9 with 5-1/2-inch back-spacing front and rear. Use tires with an aspect ratio of 40 or less with section widths of 255 front, 275 rear.
18-inch: 18x9-1/2 with 5-1/2-inch back-spacing front, 18x10 with 6-inch backspacing rear. Use tires with an aspect ratio of 35 or less with section widths of 275 front, 275-295 rear."
i don't understand how the widest you can fit on the rear in a 17 inch wheel is 9" wide with a 5 1/2" backspace, yet they say you can fit an 18 X 10 with a 6 inch backspacing. if an 18 X 10 would fit, why wouldn't a 17 X 10 with 6" backspacing?
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I know this is a very, very old post but....
The question you ask is very common in the C3 world...I currently have a '70 Corvette. C3's are limited to about 4.5" of back spacing with most wheels until you get to 18" wheels and then you can go up to 5.5" Doesn't seem logical but it works.
Up to 17" and various parts hit the wheel like the transverse leaf spring. Go up to 18" and the end of the spring goes into the wheel drum.
The typical work around with vettes is to get offset trailing arms to relocate everything more inboard. Offset arms are need for 5.5" backspace wheels from 15-17" Jump up to 18" wheels and stock trailing arms will work.
This is the best shot i could get because my McLeod throwout bearing went out as i was washing it and putting the wheels on....=\ but this is what it looks like after i lowered the front down more.
Id agree you've convinced me to go 40 series. Plus you get a better ride and more ground clearance since these cars love to scrape! I'm looking at 275 in back on 18x10 5.75bs and 255 fronts 18x9 5bs. Still researching to see if it will fit. I love the zo6 rims but the expense of spacers is a downside, on the upside its easy to make a custom offset
Did you by chance get around to getting the wheels you mentioned? I'm looking at wheels/tires of the same size and back spacing and am just hesitant on the fit.
Can someone assist me with this tire question? I have a stock 1987 Camaro with 215/65 R15 on it now. Does anyone know how much wider I can go without adding backspacers. I just want to put something wider on it. Would 225/60-15 be too wide? Thanks!
Can someone assist me with this tire question? I have a stock 1987 Camaro with 215/65 R15 on it now. Does anyone know how much wider I can go without adding backspacers. I just want to put something wider on it. Would 225/60-15 be too wide? Thanks!
Just went through this myself. I chose 245/60/15 for the rear, and 235/60/15 for the front. I want an even wider tire in the back so I will be taking the car back today to have them put on 255/60/15 on the rear. the 255's are only a little wider than 245, but they are 1" taller. I want that to give the car more rake. I'll take some more photos when the 255's are on, but this is what it looks like now with 245/60/15 on back and 235/60/15 on front. Keep in mind though that if you have stock wheels then 255's may be too wide as the back spacing is different. On stock wheels I would take a guess and say you could probably run 235/60/15 in the back, and 225/60/15 in the front. Thats what I had with my stock set-up. no wider than 225 up front though. The 225's will slightly rub when you crank the wheel all the way.
DonW, thanks for your response. I like the stance you have now, kind of what I was going for. I would like to see it with the larger tires when you get those on. Thanks for your help.
I have a 1986 firebird originally it was a v6 in was changed over to a built 350 i wanna know the widest tire i can fit on the factory wheels in rear and the set up you have is it factory rear end
Had the wheel wells trimmed inward to fit 315/30/18 tires on a Forgeline wheel with 6 in backspacing on the front and 6.5 inches on the rear. So wide tires can be put on all 4 corners.
Back in the day on my 90 Formula I ran 305 40 zr16's Mickey Thompsons on the stock 16 x 8 Formula wheels..in back only of course. I know that was probably stupid..I was young..but it looked frigging awesome!
As promised, heres pics with 255/60/15 rear put on today. Still 235/60/15 on front.
I really like your wheels and setup. I have 16" wheels and rear disc brakes on my 88 IROC. Would 15" wheels fit over my brakes without hitting? I don't have the 1LE option and I don't think i'll be upgrading them. At least there's no plans for it right now. I'm just looking for a deep wheel unlike most of the other options that we have for our cars and i'm not really wanting a Torq Thrust wheel.
Had the wheel wells trimmed inward to fit 315/30/18 tires on a Forgeline wheel with 6 in backspacing on the front and 6.5 inches on the rear. So wide tires can be put on all 4 corners.
bit of a Zombie post - sorry!
How wide are your rims? 10, 11, 12?? did you buy them based on back spacing or did they provide an offset?
How wide are your rims? 10, 11, 12?? did you buy them based on back spacing or did they provide an offset?
thanks!
Wheels are 18x10.5. Forgeline requires about a dozen different measurements for caliper clearance, width, backspacing, etc to make a set of wheels. They have the specs for these on file. They also have the specs for the 18x11s used on the DSE-Z on file. Our last order took about a month for them to make the wheels and get them shipped. Cost starts at around $1400 per wheel.
Bridgestone potenza re050a non runflats. The 305s are just as wide as a 335 michelin pilot
How do you like them? I will be running almost identical sizing but can't make a decision. I originally was going to run a PS Cup 2 335 but it was too wide, even with my mini tubs.
After years of running pirelli scorpions, michelin pilots and gy eagle f1s i have the re050a on most of my cars. I like them a lot but dont care about road noise. The purellus are just downright scary in the rain if you got some right foot. The michel8ns were ok but the bridgestones imo guve way better ferling. And they are wider for the given size. I order them in the porsche factory and mercedes amg factory soecs. M0 and n0
As promised, heres pics with 255/60/15 rear put on today. Still 235/60/15 on front.
Do you know what backspacing you have on your rims? I have stock drum brakes on mine right now and was hoping to fit 15" rims with a 5 1/2" backspace if I could. Really like the look of yours!
It depends on quite a few variables. Factory front brakes are good for about 5.5" BS. Aftermarket brakes allow for approx 3/8" additional. The limiting factor is the shape of the inside corner of the wheel lip. This is where the tie rod will interfere. I have 17 x 9 with 5.95" BS & they clear with C4HD brakes.
As you go to a 18" wheel, the tie rod fits inside the wheel allowing more backspace. The limiting factor is the strut. The wheel will hit the strut with around 6.5" to 7" BS depending again on the brakes.
The numbers you posted above are safe limits for those wishing to buy without trail & error.
As for tires, lowering the car tends to increase the fender clearance at the rear edge of the front fender due to the shape of the fender liner. My 275's hit the front rear inner plastic at full lock at stock height, but clear with the car lowered.
As for the rear, the early style rear calipers have e-brake cable issues with deep backspace wheels. The later aluminum calipers do not.
Here you will have tire interference with the front lower edge of the inner fender. A little hammering will cure this. Another issue is the bump stop which will hit the wheel with the suspension drooped. It will likely not hit during normal driving unless you like "Dukes of Hazzard" jumps & such.
I had 285/40-17's on my car (front & rear) with no issues. I plan to run 305-18's (front & rear) in the future on 10.5" wheels. They will fit, but I will be machining parts as necessary to be sure they clear.
Digging through old threads. Did you ever mount 18 x10.5 wheels? I'm looking to mount 18 x 11 wheels. I can roll the fender lip but do not want to run flares.
03-03-2016, 07:34 PM
