i have an 87 camaro with stock suspension and brakes, just wondering how big i can go while staying strictly bolt on. also i see a lot of you are running spacers. ive always heard spacers are a bad idea in a performance aplication, is that not the case anymore? im not opposed to spacers as long as its safe since there are a lot more wheels to choose from. any help is appriciated, thanks

 

We have stickies about this. And why stay with stock brakes? Not only are they inadequate, but they look stupid behind bigger wheels. Fitting bigger brakes is the reason we got 16", then 17" wheels. Not everyone thinks bigger looks better. Spacers aren't necessary if you choose your wheels wisely, and in Utah they're outright illegal. Better check what's allowed in your area. For something affordable that'll work both stock and with upgraded brakes, get some zero-offset 17x9s, like Cragar 397s. If you hit a curb hard with aluminum wheels, they'll break. Ask me how I discovered that. steel merely bends. For a daily driver, steel is real. Everyone else will suggest 275/40s, and that has an appealing look. But a 255 will actually give better handling. More predictable at the limit.

 

That is grossly incorrect, a 275 tire will give you more tire on the ground that a 255 one and should not change the "at the limit" predictability - that is more up to the tire choice than anything.

Keep in mind that steel wheels are typically heavier than aluminum and that rotating mass has an inertia of 5x that of static weight. So if you *** 5lbs per corner by going to steel 17" wheels, you added 20lbs of rotating mass, worth about 100lbs of static mass in terms of performance. You would have make the car a tenth slower with that wheel change alone, more if the tires add more weight too.

CTW Motorsports' wheels come in at 20.4lbs each without the need for spacers, about 5lbs less each than the Ronal Firehawk wheels in the same size. We even compared then to 16" 1992 Z28 wheels with the stock 245-50-16 tires, and they actually weighed 3lbs less each with a larger tire.

I'm not a fan of spacers, but if done correctly, they are pretty safe; but there is no way I would push a road race car with them on the track.

 

i dont necessarily plan on keeping the brakes stock forever. im on a budget and its one thing at a time and obviously the wheels have to come first. as far as steel wheels go im not totaly apposed but most steel wheels dont appeal to me. my car is far from a daily driver so looks and performance are king... well after the budget thing.lol

 

Can I fit 285/30/20 all the way around an 88 iroc stock suspension? Wheels are 20x9 with 0 offset. Iroc remakes.

 

thanks for the straight forward answer. my 87 is actually a berlinetta with iroc trim, cant imagine that makes a difference though? also do you have a pic? thanks again!

 

Your wrong opinion conflicts with Goodyear's embedded-sensors-glass-plate testing. Your low-res video might not show the inside edge of a 275 on a 9 dramatically lifting under max cornering, but Goodyear's tech shows otherwise. As for stability, all tires roll under to the limits of adhesion, but when the tire is trying to spring back out, that creates unpredictability. Put a 225 tire on a 9" wheel, it's already in the rolled-under attitude all the time. This makes it most predictable. But it looks lame, and it makes the sidewalls more vulnerable to potential damage. So stop posting your wrong opinions as fact.

 

So what? We're street-driving V8 musclecars, not SCCA autocrossing S2000s.

 

Thread hijack, new lady. You need to start your own thread. A 285/30 is too wide for a 9" wheel. Stop at a 265 with sidewalls that short. Then it will work.

 

What? She didn't answer you, she hijacked your thread to ask her own question. I gave you a straight answer.

 

17X 9,9.5 with 275/40-17 are about as big as you can go. 275s are always better than 255. Aluminum wheels are lighter than steel wheels therefore, better.

 

Better for what? racing? Aluminum gets destroyed if you hit anything, steel just bends a bit.

 

Better for mileage; better for handling.

 

Lol mileage? like what .05 of a gallon?

 

I'm not too interested in what Goodyear engineers do on a glass plate as none of us drive on glass. Theory sounds good, but in reality another 20mm is going to have much greater impact on handling than just a wider wheel to mount it on.

What you are talking about is sidewall stability by using a wider wheel to mount a tire, not a certain width tire vs. another, you are comparing apples to orange, sir. Maybe in a spec race situation that dictates tire width, but not wheel width this is probably true

Now if you compare a 255 tire on a 9.5" wheel and a 275 width one on a 10.5" wheel, that is apples and apples as both are wider than the section width of the tire. The 275 width tire will handle better. If the 255 handled better than a 275 in reality, then a 235 would be even better than a 255...

 

Weight kills performance that is a fact. That 100lb equivalent of rotating mass will drop about a tenth and a mph off a car's quarter mile performance. Doesn't seem like much, but do a couple of those things and you are going even slower.

I'm not rabid like some folks about weight reduction (of any make or model of car), but just look at the 5th gen Camaro: 4000lbs+ stock with a 6.2L LS3 and the cars are 500lbs heavier (at least) than the typical iron block SBC powered 3rd gen. That is why those cars along with the Challenger and Mustang have gone to a larger diameter & wider tire to give decent handling - all that mass is hard to tame. Same thing with a lean small car like a Miata or Cooper - low weight even with a small tire gives great handling - can even lump in the S2000 into that group.

Apparently some people think a 3700lb 3rd gen is ok - it's a muscle car after all... I'd rather have a 3300lb one personally...

 

I have a 1987 Firebird with a 427 cu. in. first gen sbc that dynoed 552hp. This car weights 3200 lbs. It is street legal and street driven. No, it is not a daily driver. The 275/40-17 on 9.5x17 all round are barely enough. When I get the time and money, I am going to minitub the rear. Then I am going to 9.5X18 and 275/40-18 front. In the rear I am going to 11X18 with 325/35-18.

 

If your suspension is stock, you might want to upgrade the rear suspension & chassis parts, which will greatly improve traction in a straight line. This along with a drag radial should cure most problems - there are guys running in the 7's with a 275 width tire, BTW.

 

my bad i miss read what it said. i thought i said "i can" instead of "can i".
but you didnt give me a straight answer, you just called my brakes ugly and told me what i should run not what will fit. although the tire width info was useful, ill give you that.

 

My wheels are aluminum, but I only drive 5mph so I don't have to worry about hitting a curb. Just kidding, 5mph in a third gen would be blasphemy. I do drive carefully though.

 

This car is not drag raced. It is autoX and road raced. There is not a stock suspension part on this car except the front arms. I hope to change them next year.

 

The OP's question was answered, so we can get sidetracked with Paul Huryk's nonsense. Going from a 245/45R17 to a 315/35R17 gains you nothing but drag. You don't gain desired contact patch, because that is a function of weight. So as the weight stays the same and the tread gets wider, the contact patch gets shorter. Basic physics.

 

your car is not going to handle good with bigger size tires in the rear and smaller up front, third gens like the same size all around.

 

Not that it matters, but as a side note... I don't think all spacers are illegal in Utah. If they are a pure spacer that reduces the length of the studs then they are illegal... if it is one of the bolt in spacers that has its own set of lugs then it is okay.

 

I have 20x9 rims with 0 offset on my IROC. I have 285/30/20 on the back and 255/30/20 on the front. The backs fit great and I have a lowering kit sitting in front of me ready to go on and I still think they'll fit well. The fronts I get a tad of rubbing on the inner liner at full turn. I think I can maybe heat it and bend it, but I don't know if 285's would work okay up there. Remember 285/30/20 is an inch taller tire than stock 245/50/16 and half an inch taller than the 255's that I get slight rubbing with.

 

I'm not condoning spacers of any kind, not by a long shot but.....What about the FACTORY slip-on spacers? Was GM building only-49-state legal 3rd gens then?

 

...good point. All I know is what I read in the safety inspection manual. im sure if you could show it was stock they'd pass it.

 

I hope that is sarcasm as my supply of nonsense is non-existent.

Question is: what makes you think that a smaller tire makes the third gens handle better when it has been proven that the bigger the tire, the better the grip and overall handling? I have read more than a few articles where going from a 245-50-16 tire to a 275-40-17 one gives the car more grip and control. And I guess that all the new cars (like the new ZR1 and ZL1) should be on 245 width tires for better handling too?

Also, you talk about some Goodyear findings like it's gospel and then tell us that weight doesn't matter? Your joking, right?

 

Dynamic loading: Load transfer, often wrongly called weight transfer, is much of why extra-wide tires can sometimes be some help. But as the effective contact patch grows, the contact pressure decreases. How hard each square inch of tread is being pressed into the road is far more important, as the Caparro T1 proves. The T1 is a recent development, using sticky Pirellis and ginormous amounts of aero downforce to be the only road-legal car capable of more than 1.5 g cornering. It's capable of twice that, on those sticky but legal Pirelli P-Zero Corsas. Put those same Pirellis on our cars, in ANY size, you still won't exceed 1.5g. I gotta go, I'll finish this fallacy-correcting tutorial as soon as I can.

 

87350,
I would pick a wheel that "you" think looks good and fits your application from this thread and then see if it fits or can be made to fit.Its that easy.
https://www.thirdgen.org/forums/whee...g-3rd-gen.html

PS. Some of the photos have been taken out but you still have many, many pages to look at.
PSS. Here's a suggestion,start looking from the last page and work your way forward. The newer posts don't seem to have the missing photo problem. Enjoy

This is my last edit .
This thread dose is not about wheels but has some beautiful choices. You can copy and past photos between replies on this site.
= https://www.thirdgen.org/forums/auto...your-best.html

 

Well, I think you are right about the contact patch of a tyre being the same as long as the weight and tyre pressure are the same: P=F/A so A=F/P, F is the weight of the car, P is the tyre pressure, if F and P are constant then so is A.

But now you are saying that as the contact patch grows the contact pressure decreases, that is true, but how do you increase the contact patch without changing the weight or the tyre pressure?

 

will 2012 camaro wheels fit on my 88 iroc

 

Please use the Search feature that is built-in to TGO.
https://www.thirdgen.org/forums/whee...amaro-5th.html

 

C6 Wheels 17x8.5 would those fit my 3rd gen?

 

Wow is all I can say. There is so much crap in this thread its not even funny.

Tire width.
Atilla, the point you are making includes a bunch of assumptions that aren't valid to tires. Tires propel, turn, and stop a car by resisting sliding. This is grip, or in science speak, frictional force, Ff. In classic RIGID BODY physics Ff = mu (coefficient of friction) * Fn (normal force). The coefficient of friction in RIGID BODY physics is a material constant and depends on the compound of the tire. The normal force is the weight on the tire. So according to RIGID BODY physics, I agree with your assessment that the tire width doesn't matter.

The problem is, tires are not rigid bodies. In fact they are quite soft. In reality the coefficient of friction of rubber DROPS as the normal force increases. The higher the load on a section of the tire, the less it will grip. That is why wider tires grip better in a turn.

Aluminum vs steel wheels:

Aluminum is always the better choice. It has a higher strength to weight ratio than steel. You can easily design an aluminum wheel to be stronger than a steel wheel and vice versa. Remember aircraft are primarily made of aluminum. Aircraft are used 14+ hours a day for 30 years straight. There is no risk of additional problems using aluminum when designed correctly.