Ok, I am not satisfied with the traction my Camaro gets. I want to get wide tires on the back, and I want it to look good to.

I have been doing a lot of reading on this subject and I have read through all these threads (Didn't necessarily understand it all)

https://www.thirdgen.org/forums/susp...er-wanted.html
https://www.thirdgen.org/forums/susp...18-wheels.html
https://www.thirdgen.org/forums/susp...ight=ZR1+56+MM
https://www.thirdgen.org/forums/tran...?highlight=295
https://www.thirdgen.org/forums/cama...ew-wheels.html

Ok, so this time I really did do my research.

Now, with all stock ride height, and an Iroc nine bolt rear (with disks) I can run 4 ZR1 wheels(17 x 9.5 / 56mm), with 285/40R-17 tires on the rear, and 275/40ZR-17 on the front, with 2 inch spacers all around, right?

Now, in one of the other threads, it was mentioned that spacers are not desirable, why is this? Is it more critical front, or back?

If I run a fourth gen rear, then I do not need to run spacers, right?

Ok, one last question. Someone mentioned 315s on the rear, but I was on the Discount Tire site, and I couldn't find anything larger than 285, am I shopping on the wrong site, or is anything past 285 hard to find for reasonable prices?

I will be honest, a huge part of why I am doing this is so it will look good. Traction is important, but I know I will be putting the most discount wide tires on the back, that way I can bake them off without crying!

 

56mm backspacing will require 2" spacers front and rear, unless of course you are running a 4th gen axle.

There is nothing wrong with wheel spacers as long as they are bolt-ons. A slip on spacer acts as a lever on the studs and WILL break off the studs eventually. This has give all spacers a bad name. Bolt on spacers load the studs on the sheer plane and elminate this problem. They are as strong as the wheel you are bolting to them.

You can fit a 285/40/17 on the front of the car, as long as you are willing to do a little trimming of the ground effect and heat and mold the rear inner fender plastic a bit. I would try my best to have the same size tire front and rear so that you can rotate them. You'll get much better wear out of them as the rears will tend to wear the center and the fronts will wear the edges of the tire.

You are probably not seeing any 315's because you are searching under the 40 series tires, try looking under the 35 and 30 series tires. With that said 285's are as wide as you want to go on a 9.5" wheel. You'll need 17x11 wheels for the 315's, lots of hammer work in the rear and even then they'll still stick out a tad too much for my taste.

It's good to see you doing your research, that's a rare accurance around here. I know I'm more willing to help a guy out if I see that they have put forth the effort to find the information on their own.

 

Well, for me, being a high schooler, I like to show off and bake the tires regularly, so I go through rear tires alot faster than fronts, and I have a phobia of taking a hammer to my baby. (Hence, I will probably never rotate my tires)

Bolt on spacers, do you have to modify the studs for clearance issues? The only reason I ask is that I would like to keep the wheels if I ever sell the car, and I had to cut off part of my studs then that wont be as easy to do.

With me NOT wanting to modify the front wheel wells at all, what is the widest I can safely run?

The the 245s I have all around now, will I notice a big difference going to some 285 rears?


If I wanted to get some 295/30, that would mean a smaller sidewall, which would look funny, right?

 

Ok, so I need to re-do my springs on my Camaro any way, and I was talking to the guy at Jegs, he said this is the kit I want.

http://www.jegs.com/webapp/wcs/store...0002_739010_-1

It lowers the car one inch though, but its alot stiffer, will I be able to run 285/40/17 rears and 275/40/17 fronts with this kits, or will I rub all day and night?

 

www.Tirerack.com (discount tire has poor selection)
Go 315's!, search user 1meanz, he has them and they look badass! I'm sure he can give you a lot more info too.

I have 275's up front with a 2" spacer, no rubbing at all, even at full lock! You will probably rub at full lock if your car is lowered, however.

 

Thanks a million. Kinda funny, sounds like he is just a few months ahead of me, but it looks like he did the same build as me! Stroker 383, but worried about traction.

Ok, the more I think about it, the less I want to lower this car, I just don't have much experience with suspension, I just know mine is 16 years old with 200,000 miles on it, and I think the car WANTS a suspension re-build. What needs to be replaced with what? Darned if I know.....

 

Ok, wow, how my engine build has evolved into a complete overhaul, I dont know, but its going to be fun!

So, this is my understanding. 315s can be run on ZR1s, it has been done, with no wheel well modification. The problem is, as I get more and more outrages, the less available information is. None of my searches have told me what size spacer I will need for sure.

I dont understand spacers completely, do I have to modify my studs?

I think I will probably order a few sizes, and then E-bay the ones that I don't need, hopefully I will get what I paid back out of them.

Can I go 12 inch rear tires? I think I can, I think I can, I think I can.

 

The spaces will bolt onto your existing studs in the axle, and then they have studs of their own for the wheel/tire to bolt to if I am not mistaken.

 

The reason you don't see things spelled out like you want is that the information to figure this out on your own is readily available.

Go find out how to :

Calculate your actuall backspacing based on the offset of the rim, then go measure your car now and see how much room you have. This will tell you how big you can go.

Then go find out how to calculate the actual size of the tire. Hint: the second number in the tire size is a percentage of the tread width. Which means that a tire isn't necesarrily lower profile because this number is smaller.

Go re-read what it takes to fit 315's UNDER the fenders, he had to do quite a bit of hammer work to get them to fit. Also, you have to get 17x11's to properly fit 315's.

The point of being able to rotate the tires is that you can evenly burn off all 4 tires so that you aren't running aorund on 2 bald tires.

 

another link for you: www.skulte.com
He will take care of ALL your adapter needs and questions.
I believe it is a 1.25" spacer for 11" ZR1's.
Check the FAQ link on his page, he has a chart showing what adapter sizes popular wheels (including 11" ZR1's) need! Highly Recommended!

 

Thanks! Just sent him an E-mail, on his site it says that the 2 inch rear spacers are recommended, or a fourth gen rear.

I am planning a rear end swap any way, just because I want rear dicks and a 3.23 posi, but I want to know if the Nine bolt Iroc/GTA rear and spacer will be stronger or if I should use a 10 bolt out of a fourth Gen Z28?

Also, this will sound stupid, but what is it in the rear end that is the determining factor of its "strength"? I am going to be running 400 horse power, and I have heard of 4rth Gen LS1s snapping the rear end under stock power!

 

The strength factors of a rear end are; the size of the ring and pinion(actual measured size), the size & alloy of the axles, and the rigidness of the rear housing itself.

The 9-bolt housing is stronger than the 10-bolt, thus it doesn't flex as much. Less flex = less deflect between the ring & pinion, therefore less chance of breaking the gear. The stock axles have taken the abuse of several 11 sec cars, some 10 sec. - BUT, parts availabilty for the 9-bolt sucks.

A ten bolt with a decent aftermarket gear, solid pinion spacer, and decent axles will hold up well with as low(numerically high) as a 3.73 gear. Mine with stood 5500+ rpm clutch drops running 11.7x's and other on here are running in the 10's, but are running more aftermarket parts. Parts availabilty is much better. - BUT, the stock c-clip axles are fairly weak and anything lower(numerically higher) than a 3.73 will not live long, as the smaller pinion will not tolerate as much flex, but it creates more flex, thus it is the death of itself.

Skulte seems to be the adapter of choice and they guy(Andis?) is know for being very helpful.

 

Yes a 2" spacer is what's needed for a 17x9.5" wheel with 53mm offset.....it won't work for a 17x11 with a 53mm offset, do you know why?? Do some research and figure out what all these numbers mean, you'll answer your own questions.