I am completely redoing my whole car and the look I want requires new wheels. As far as I can tell, I should go with 18" wheels so I can have more clearance for tie rods and stuff like that? Originally I wanted to go with 17", but after reading it seems the 18" wheels would work better.
Ideally and if it is anyway possible at all, I want to run 18"x10" in the front and 18"x12" in the rear. Front tires being 295 and rears more like 315 to 335.

BFGoodrich g-Force KDW-R Tire
Forgeline TA3 Wheel


I need help figuring out what I have to do to make these work. What offset/backspacing? What do I need to clearance on the car? The hardest part I have found while doing research is that I need to keep my rear seats. So I can only tub it so much. (How much is that?)

Any help will be very much appreciated. If you find some links or something that I didn't than please post them and I will go read them. Just trying to figure it out so I can go buy some more parts to get the project moving forward.

The rear end is going to be the Hawks Custom 8.8" that they make bolt-in for our cars. Looking to run the factory 3rd gen length, unless I can shorten it to be able to fit the wheels and tires back there better? Wheels must have a lip in the rear if anyway possible.

Hawks 8.8" bolt-in rear-end


If it matters, the front brakes are going to be Baer Pro+ Front brakes with the 13" rotors. And the rear are going to be Bear Rear SS4 brakes with the 13" rotors as well. (Looking to do dual rear calipers, the second one being for a hydraulic handbrake; so might have to go with the 12" rotor in the rear.)

Front brakes

Rear brakes Blue Ice


Thanks in advance for any help and/or advice.

 

I think that they will be too wide for the front and rear. I am looking at having my rear wheels widened to 11" and after some research I will be into some definate inner wheel well modification. Unless you want the wheel sticking out of the wheel wells. I think 10.5 is about as wide as you can go without modifications.

 

I have no problem with a small mini tub and fender flares as well, but would like as much as possible under the car. If a 10.5" wheel fits without mods, then I should be able to get 12" (only 1.5" more) with some slight mods. Maybe pulled and rolled fenders?

 

Nothing slight about fitting a 12. You need a serious minitub to properly clear a wheel that wide. I'm running a 18x12 with a 335/30/18 on my 86. The control arms get in the way too

A 10 or 10.5 will fit the front, but it's really tight to do it right. I would advise building the suspension and brake package first and measuring then. And discrepancy will make for poor fitment.

From what I've run, on my 92, 5.95" of backspacing will fit a 18x10.5 on the front with the stock 10.5" brakes. They will rub the front and back of the wheel well a little at full lock, require added camber and the extra clearance of an aftermarket a arm helps too. The back of the stock a arm gets close to the wheel. The tie rod will be close, I don't remember if it fit as I had rod ends for my outer tie rods and a altered steering arm.

 

Everything I have researched and looked into you have been there and I see you are running the sizes I want. Can I tub the car at all with keeping the rear seats? What about the rear end? Do I need to have it shortened any?

I already have UMI road race K-member, arms, sub-frame connectors, wonder bar, and strut mounts on the way; as far as upgrades go for the chassis and suspension.

Any help or advise or specs would be so much appreciated from you.

 

A 10" wide wheel is not hard to do - 5.75" to 6" BS on all 4 corners.

A 275 or 285 is plenty wide for a 3rd gen square setup, 295 is nice also. The amount of work you have to do to get a 12" to fir under stock bodywork may not be worth the effort.

 

I found an older sema build where he widened the fenders/quarters 1.5" to get 12" in the back of a 1990 Camaro. Would that be needed if I did tub it a little bit?

Am I right in reading a 10" to 10.5" will fit in the rear without tubing it? I have never done tubs in a car before, but I would think by just thinking about it.. If I can tub the car for the other 1.5" shouldn't it work? I'm sure I am missing something that you guys are telling me.

The new engine set-up is starting out at 660ftlb so I would like more than just the normal 275-295 back there.

 

I will add this. Take a look at tire sizes. In the 295/35/18 size there are a million options. After that size, almost nothing. That's one of the reasons I decided to do 4- 18x10.5 on my 92. I like the fat rear tire look I have on my other car, but the options for tires is rather slim.

If you flare the quarters, you will minimize the work needed to the inner wheel well, but at a higher cost since the body work has to be done cleanly and repainted. I chose to keep mine fitted like stock, and because of that I lost the rear seat, which doesn't really matter to me, nobody rides back there.

1.5" in is a lot, you have to cut to the side of the shock mount pocket under the carpet if you need a point of reference. My cut mark was partially through the hump in the spring pocket that located the rear insulator, so obviously the stock spring can't go back in, you would need to use coilovers or a smaller diameter spring rigged up in the stocl location.

With almost 700ft lbs of torque, a 335/18 still won't do much if you mash the throttle, I only have 520lb/ft and mine get murdered through 3rd gear if you get on it.

 

Will the 10.5" wheel fit all 4 corners without mods? Or at least major mods? If that is what I can do without body work than maybe I can start with that. As the wheels are 3 piece I can get them redone at a later date. I am going to have to have body work done as the car was hit a few years back and it will need paint once I finish the build anyways. But I can run the 10.5" for now for sure?

 

6.42" of BS or +17 fits the rear with only minimal hammering, provided the rear is centered. That's a 18x10.5.

5.95 fits the front.

These numbers are based on my fitment, the rears are a little further out than stock, so maybe roll the fenders if your that low or if you suspension is soft. There is a little wiggle room but not much. If you use longer wheel studs you can add small spacers to adjust for any fitment issues cause by not having the exact offset abailable. I got creative and had custom hubs made by kore3 so I could run 4 identicle wheels in my 92. They were 18x10.5+27. Ran a 10mm spacer in the rear and the custom hub on the front with no spacer. It's was a beautiful setup and fitment was great. Just sold the hubs, still have the wheels and tires. Not sure what I'm doing with them yet.

 

Thank you for the information. As far as the wheel spacers; are they needed? I would like to not run them if I can. I figured since I am having them custom made that I could avoid that and just get the exact backspacing that will fit correct without it.

Is your rear end factory length? So these will fit with a factory length rear end?

 

On the rear you can fit by rolling the fenders and beating the inners some lots of threads on here have details rn third gen or 4th gen width, I would recommend 4th gen width on the rear which then wouldn't need spacers with those wheels.

 

If they are 3pc wheels, they can be made any way he wants so why would he need spacers??? If you run a 4th gen rear, you need to run large spacers up front or else the rear wheels have no lip and the front does. Looks stupid.

 

Well, like i said, if you can get them made exactly how you need them, then no spacers are needed. I will also say again, if you are buying a front brake kit and new rear axle, I would wait until you have them and they are installed before ordering wheels in case there are any differences in track width caused by the new parts. I would hope Hawks made the rear the same width as stock, but a small variation of even a half inch overall will mess up your wheel fitment if clearances are tight already.

Also, with these power levels your aiming for, are you sure the 8.8 is up to the task? I'm pretty sure you can buy a Moser 9" (or other brand 9' setup) with an aluminum 3rd member for a similar price and it's a stronger rear.

As for the front, baer has a habit of making their parts proprietary and may alter the hub offset one way or another so that it doesn't interchange with any stock or aftermarket hub, so who knows what the parts will do to the front end width.

I alway a run 3rd gen width rears. There is no reason to run a wider 4th gen rear since then you are forced to use front spacers to use similar style wheels.

 

I will be waiting until I buy the other parts before ordering the wheels. I just want a starting reference instead of going in with no idea.

Hawks 8.8 comes in 3rd gen length, 4th gen length, or custom length. As far as it being strong enough; Bruce (I think) has conformed that it will hold up to my power rang and then some. As far as I understood it he is running it in his personal car, something like 7**hp and 7**tq. They have one rated at 1000hp. I'm just a little worried because everybody always rates everything at horsepower numbers while I am going to be making more torque.

The research that I was doing was saying even though the 9" is stronger that the 8.8 can be made pretty close to the same strength and it always robs less power; more efficient.

 

As far as rear ends, the 9 inch is cheaper than the 8.8 from hawks. Look at quick performance for one. They quoted me $2500 shipped for one rated at 800hp. That was complete minus brakes.