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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!
i've read a lot of the old posts on this topic, but don't see a real consensus. wouldn't this make a good sticky? in the tpi section, they have a "tpi faq" sticky that they direct newbies to.
in the tech section, under "andris skulte's wheels and adapters faq", it says: "The 89 Camaro can fit rims with a maximum of 5" front and 5.85" rear backspacing."
on the car craft magazine website, there's a link to an article entitled "fitting tires and wheels". it's based on research done by weld wheels and is supposed to be the bottom line on what can fit. here's what they say about third gens:
" 1982-1992 Camaros and Firebirds
15-inch: 15x8 with 4-1/2-inch back-spacing front and rear. Use tires with an aspect ratio of 55 or less with a section width of 255.
16-inch: 16x8 with 4-1/2-inch back-spacing front, 51/8 backspacing rear. Use tires with an aspect ratio of 55 or less and a section width of 255.
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?
if you wanted to get the widest wheel possible under the front and rear of the car and you wanted to fit them as far inside the wheelwell as possible, what would the size, width and backspacing be? how is this affected by lowering springs?
i see a lot of people asking those questions, but not many solid answers. wheels and tires would have to be the most popular upgrade to any cars, i'm sure third gens are no exception. why doesn't everyone who has put wheels and tires on their cars and / or has technical information on what you can do post it here? then we can make a "wheels and tires faq" and post it on a sticky.
I have 16x8 rims with 255/50/ZR16's all around. But I wouldn't go any higher then 255 in the front. I had 265/50's once with my 15x7's and if you turned the wheel all the way they would rub slightly.
Well if you want to know the maximum wheel/tire sizes possible you should be concerned with the size of the wheel and tire combined, not really with the size of the wheel itself or the tire size. Once you find the maximum overall size, then you can find a wheel/tire combo that fits within the maximum limits. I dont know if you mean by height (wheel size and sidewall size), or width (tire width), or maybe both. Unfortunately the maximum size tire that fits will have alot to do with the stance and suspension setup of the car. Because everyones car has different suspension parts, its hard to come up with a maximum size for everyone. Stock stance will be alot more forgiving than a 2 inch drop for example. Another thing would be (like you mentioned) the offset. A custom offset might allow you to run wider tires. Alot of variables that make it hard to come up with something that will work for everyone. Not saying its impossible by any means, but would take alot of research. I think it would be usefull to have a sticky for the suspension forums, sort of like the stickies the other forums have. There is alot of suspension information on these boards, combos that work, suspension geometry theory, brake upgrades, it goes on and on. The search tool is the key to finding the info. I play with it often
Chevy High Performance had an article awhile ago on stuffing the fattest tires under all four corners of your camaro, and it said that the biggest wheels you could put on a camaro were 17x9.5s with 5.5 in backspacing.
The key is the 5 1/2 " back spacing. You have a 11" width within the fenderwell in the rear that is a safe "zone" for suspension travel. The front is 10" for the safe "zone" for turning and suspension travel.
You can roll the inside wheel opening to gain a little, or add fender flares on all four corners.
But as I said, 5 1/2 inches is he deepest starting at a 16 inch wheel diameter. Any more you are going to need wheel spacers.
Thanks for bring that up 'todillinder', people where thinking I'm nuts with wanting to stuff 15x10 / 24"-26"dia? under the front.
Right now I have a couple of Aero wheels with 5" BS, no tires yet.
Real turd trying to get Goodyear G19 or other race tires in my area.
Just eyeballing it, it looks that the rear is no problem. The front might need a spacer cause it's way close to the strut. Being the rims actually measure 11" bead to bead, the tire I chose will more than likely be 11" as well?
I'm going to research hard on the actual tire that I will go with, and than set up the rear. I will see what needs to be done on the front by test fitting the rears.
My goal was to run identical rims & tires on all four. Again - series 51 Aero Wheels w/15x10 5bs
No doubt on the fender flares, just eyeing it with no tires & the left side jacked up, I could tell flares are in order. The fronts do look like they might need some cutting on the inside. I didn't see to many problems with hitting any suspension parts, but the front fender support might need to go. Again I just eyeballed it...
Ronterry,
You mentioned the Goodyear G19's. Those are able to run on 15"x 7" wheels, the tires like 8" up to 10" wide wheels. They are not as "squishy" with the wider wheels.
With a 15" x 10" wheel in the front you are going to need a wheel spacer because of the brake lines, strut, and the tie rod end. the tie rod and brake line will get bound up with a 15 inch diameter wheel. It is just the way it was designed.
The overall width of the tire would measure between 10 to 12 inches depending on the amount of air pressure and actual weight in the front that the tire is supporting.
Get a copy of Grassroots Motorsport magazine, in the service ads in the back are numerous tire suppliers that you could contact. It would tke a couple of days, but I had the number for Compitition Tire in Brooklyn, Michigan. CT is the factory distributor for Goodyear. You could also check Goodyears website to find a dealer for race tires closer to you.
Good Luck,
Todd O. Dillinder
Production and GT class Chairman - Midwestern Council of Sports Car Clubs.
Owner - Dillinder Racing Enterprises
both, does it make a difference? i have the drums on right now but i have a complete 3.73 disc rearend in my garage that i was planning on putting on in two-three weeks.
With the 15" wheel clearance problems with the bracket on the rear and housing (panhard bar on driver side). You might have a clearance problem with the caliper and /or the brake line, depending if it has been modified. For the rear it is best to test fit and double check, I do know 4 1/2 inch backspace is safe on the rear.
Now the front is a different issue. With the 5" backspace on the 15" wheel, you will rub against the strut during cornering, and bind against the tie rods in turning. Front max backspace with a 15" wheel is 4", you might be able to get away with 4 1/2", after twelve hours at work last night I can't remember seeing anyone use a 15" wheel with 4 1/2" backspace. Again test fit to double check.
Needed to know if you had aftermarket calipers for the brakes.
Some calipers are made to where you have to use a 16" wheel or larger.
it's the stock disc brake rearend off of an 84' z28. the front will be a 15x4 so i shouldn't have any rubbing problems, the backspacing on those is like 2 1/2". the calipers are stock as well so i think that a 15x8 with 5" backspacing will be ok. i am more or less worried about my tires rubbing the inner fender wells. my BFH will fix that problem though.
If I use the adapters from Thunder Racing, can I put my 1998 Corvette wheels on my 1989 Formula WS-6 lowered 1 1/2 inches. What would maxium tire size be for the 17 and 18 inch wheels then?
Originally posted by jdaniel If I use the adapters from Thunder Racing, can I put my 1998 Corvette wheels on my 1989 Formula WS-6 lowered 1 1/2 inches. What would maxium tire size be for the 17 and 18 inch wheels then?
9.5 " wide with 5.5" backspacing on all four corners, no mods to body. While in California at a NASA event at Buttonwillow, there was a third gen Camaro ( American Irons Series Extreme) using 17x10 w/ 5.5" backspace front and 17x11 w/ 5.5" backspace in the rear. However, the wheel openings were reworked in a custom fashion.
Todd O. Dillinder
Prod and GT class Chairman - Midwestern Council of Sports Car Clubs
Owner - Dillinder Racing Enterprises
I have 275/40-R17 tires on the back of my Firebird and there is gobs of extra room for wider wheels and tires. Wish I knew that before I bought all that stuff. I do not have ground effects.
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?
if you wanted to get the widest wheel possible under the front and rear of the car and you wanted to fit them as far inside the wheelwell as possible, what would the size, width and backspacing be? how is this affected by lowering springs?
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.
Last edited by Lonnie P; Dec 25, 2012 at 11:07 AM.
yeah I'm running a 4th gen rear as well but with 18X11 Ruff racing rims and 295/35/18 its all under the fender but its TIGHT, I can fit 315's but that would be the absolute max. Issue I have is that since the car is a convertible the tire bottoms out on the top of the wheel well which is lower due to the top storage. and I'm running factory ride height.
The post you put on here a few years ago from car craft, were these sizes and offsets based on rear disc brakes or rear drum as disc brake rears sit out further.
89 camaro with a 4th gen rearend. Can I fit a 275/60/15 on a stock 3rd gen wheel in there? I know it'll stick out..I'm ok with that as I'm going to change wheels eventually.
Regardless of what rearend you have on your car, I would not stick a 275 width tire on a 7" wheel (stock size). I would not go over 235 on those. At the minimum, you would need a 9" wide wheel to mount a 275 tire with confidence.
Originally Posted by WickedBowtie
89 camaro with a 4th gen rearend. Can I fit a 275/60/15 on a stock 3rd gen wheel in there? I know it'll stick out..I'm ok with that as I'm going to change wheels eventually.
1990 IROC with Cray Brickyard 18x9.5 front and rear with 275/40-18 they are designed for a C6 with 7.5 inches backspacing. i have 1.75" spacers up front and 1.625" spacers on the rear. i also have QA1 coilovers all the way around and it is lowered quite a bit (not sure how much) but i don't think the coilover helped nor hindered the clearance of the front. the fronts BARELY touched at full lock both ways so i took a heat gun to the plastic splash guards and bent them out slightly and tada! no more issues. it is pretty tight between the coil and the tire but not enough to be a problem.
inner clearance. i only had to beat in the front inner side of the fender well a little bit
for visual purposes haha
the front has since come down a bit to level it out. still no rubbing.
1990 IROC with Cray Brickyard 18x9.5 front and rear with 275/40-18 they are designed for a C6 with 7.5 inches backspacing. i have 1.75" spacers up front and 1.625" spacers on the rear. i also have QA1 coilovers all the way around and it is lowered quite a bit (not sure how much) but i don't think the coilover helped nor hindered the clearance of the front. the fronts BARELY touched at full lock both ways so i took a heat gun to the plastic splash guards and bent them out slightly and tada! no more issues. it is pretty tight between the coil and the tire but not enough to be a problem.
inner clearance. i only had to beat in the front inner side of the fender well a little bit
for visual purposes haha
the front has since come down a bit to level it out. still no rubbing.
I think the way the tires fit in the rear wheelwell is dead-on perfect.
Do you have any pics of the front since it dropped?
No, I do not. The weather started getting crummy cause off all those storms so I put my IROCs on with my winter tires. As soon as I get the Crays back on I'll post a pic on here for ya. On a side note, I have to remove the rear wheels by jacking up the car by the axle. If I let the suspension travel extend the wheel hits the bump stop. And the front coil over spring is actually "free" about an inch when the suspension is extended as well. Eventually I will get a longer spring and remove/relocate the bump stop in the rear but I'm not in a hurry for that right now. It's not affecting anything. Here's the car with the IROCs though. The gap is essentially the same with the Crays.
1990 IROC with Cray Brickyard 18x9.5 front and rear with 275/40-18 they are designed for a C6 with 7.5 inches backspacing. i have 1.75" spacers up front and 1.625" spacers on the rear. i also have QA1 coilovers all the way around and it is lowered quite a bit (not sure how much) but i don't think the coilover helped nor hindered the clearance of the front. the fronts BARELY touched at full lock both ways so i took a heat gun to the plastic splash guards and bent them out slightly and tada! no more issues. it is pretty tight between the coil and the tire but not enough to be a problem.
inner clearance. i only had to beat in the front inner side of the fender well a little bit
for visual purposes haha
the front has since come down a bit to level it out. still no rubbing.
Those look nice man! I've been searching for a pic of 275/40s as most go with 275/35s. The 40s are an inch taller and I was wondering how they would look. What springs are you running? It seems to me a taller tire would require less low to get that sweet fender to tire gap
personally, i think the 40 series looks much better. i know it's not much but that subtle difference makes the wheels look like an actual "performance" tire instead of a 24" rubber band...just my preference. it has coil overs. 10" 350# in front and 10" 175# in the rear. the taller tire would help with the gap but at the same time it's harder to get the car lower to the ground without losing the gap all together.
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
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
within the constraints of what i had said, these are options specifically designed for certain brake caliper clearances. different pad heights combined with offset make the backspacing and clearance to the brakes needed for the ideal look.
