Xsta Z 28

iTrader: (2)

I do not see why you would have any issues after doing that.

allthrottle&nobottle

Yes, you must do this.
You can use any other wheels also with no problems, I use 4 other sets of wheels with no problems.
I have this drag pack on my 97 also





good luck

LS1Lust

I have a quick question. It looks like I will be fine from reading the fist page of this thread, but just want to make sure before I move forward with my current plan.

I want to take an 18x9.5 wheel with a 45mm or 42mm offset and widen it to an 18x11 wheel to run 315/30x18 tire.

Will I have any problems? I don't want to have to BFH it too much and I don't want to roll the fenders. Also would this effect the ability to lower my car down the road? I am looking to run Sam's spring which I think drop the car about 1.3in. Would these cause a problem?

Also I have heard that getting an adjustible panhard bar is almost nesecary to run such a large wheel tire combo. Is this true or will it just make life easier?

Thanks,
Alex

sc300ccret

Okay, So I'm about to drop serious cash on some Iforgeds and I have read all 37 pages of this thread. Here is what I can't figure out. Offset

I'm going to go with 18x9.5-275/35/18's F and 295/35/18 Rears on a 10.5 inch wheels.

The car is a 99 Trans Am. Its at stock height for now. For offset I'm thinking a 42mm in the front, and a 50mm in the back. I'd prefer to BFH over Rolling a Lip. Does this offset seem correct? And worst case if the wheels are "sunk in" too far I'd just get a few mil spacer to fix it. Seem rational?

Mike

Xsta Z 28

iTrader: (2)

The 9.5" wheels with the 45 or 42 mm offset will fit fine. Once you widen tham the offest will change accordingly. Since you'd be adding 1.5" to the rear of the wheel, the centerline fo the wheel will move .75" or about 19 mm. So, 42 mm = 19 mm = 61 mm so a spacer would be needed of about 12 mm.

Xsta Z 28

iTrader: (2)

Front offset is fine. @ 42 mm. I run 38 mm 9.5's.

In back the 50 mm is a little conservative. I too run a 38 mm on my 10.5's but that is VERY aggressive. There too I'd say 42 would be fine as well.

LS1Lust

So would it better then to try and get a wheel with say a 30mm offset? Thay way when I widen them they would be about a 49mm offset. I keep hearing bad things about spacers. Is 12mm safe to run without longer studs?

Alex

Xsta Z 28

iTrader: (2)

The 30 mm would be better.

12 mm spacers DO NOT work with stock studs. That's nearly 1/2" think.

LS1Lust

I am thinking an 18x8.5 up front with a 35mm offset. In the rear I am thinking about an 18x9.5 with a 35mm offset. When I widen it to 11 that should increase the offset 19mm giving me a 54mm offset which should work fine right?

Since 54 is towards the higher end of the range that puts the wheel farther inside the wheel well right? The inside of the well is where the BFH comes in? Because I think I would much rather do that than roll the fender. Also 54mm won't push them in to far will it, it is one thing for them to fit but I don't want them to look funny either.

Alex

intheclouds1977

I just installed (today) 18x10.5 wheels with +58mm offset. For this wheel, there is 7.5" of wheel inward of the mounting surface.

For a 18x11 with +54mm offset, you will have 7.6" of wheel inward of the mounting surface...just barely more than what I had. I am running 295 tires.

To get the wheel/tire combo to fit, it took the BFH on the inner fender. The tire is in plenty from the lip so that I won't have to roll it. However, I also had to unbolt the bumpstop, and sawzall the bumpstop mounts off of the inner fender. If you're not prepared to cut off your bump stop mounts, you will definitely need less + offset or a spacer.

The bump stop ran into both the tire and the wheel. It held the wheel about 1/2" out from the mounting surface until I cut it off.

LS1Lust

Great info, thanks! What does getting rid of the bump stop do? Isn't it what stops your suspension from traveling to far? Also from reading around it sounded like you didn't have to get rid of it if you bolted up the wheels when the suspension was loaded. But i guess it could still cause problems if you hit a big bump/unloded the suspension while driving?

Do you have any pics of either the install or just your car with the new wheels? I know the 315's will look different but might be good refrence

Thanks again,
Alex

intheclouds1977

The bump stop limits the compression of the suspension. You should NEVER reach this point driving a sports car. The only time a bump stop will touch the axle is when loaded down. If I wanna haul loads, that's why I have a truck. No worries for me losing the bump stop.

As you stated, I probably could have mounted the wheel with the suspension loaded. The bump stop may have tucked inside the rim. However, if the rear suspension ever full drooped, it would cause major damage to the wheel. I didn't want to take the chance. Who knows what crazy driving I may do some day or what bump I may hit that would cause the suspension to droop. This is why I chose to remove the bump stop, not tuck it in the wheel.

I'll see what I can do tomorrow to take a few pics. I didn't take any during the install.

LS1Lust

Cool thanks again. I look forward to seeing some pics.

Alex

intheclouds1977

I just thought of one more thing. You can hammer the fender well...but you can't relocate the control arm. I'll put a measuring tape up in a picture to show you the clearance to the control arm (there isn't much). Not sure if a 315 would fit (tomorrow will tell). You might need a small spacer to clear the control arm.

LS1Lust

I was thinking an adjustable panhard bar would help. Make sure the car is nice and centered before I try and tuck thoes things back there

intheclouds1977

Pictures as promised:

This picture shows the clearance from the tire to the hammered fender. You can see where the bump stop was attached and has been cut off.



This picture shows the tire to control arm clearance.

LS1Lust

Thanks for the pics, man this is a pain

blackmaro99

iTrader: (5)

I apologize in advance since I have no doubt this has been asked.

I'm looking at running 17x11 ZR-1 Replicas in the back with 315/35 R17 DG-S3's. I'll be installing these on a 1999 Camaro SS which is not lowered.

Will running the +38 offsets save me from BFH mod and/or fender rolling, and will it be just as safe/practical or would you recommend the +50mm? Also will I need the adjustable panhard bar?

Xsta Z 28

iTrader: (2)

I do not reccommend the 36 mm offset fro the rear of the Camaro. They will stick out of the wheel well and guarantee quarter panel issues.

50 mm is your best bet, and may require inner wheel well mods. Rolling the quarter may not be required and is purely dictated if you are lowered.

blackmaro99

iTrader: (5)

I'm not lowered and I have no plans to do so. Is the BFH mod something that I can do safely without worry of damaging anything? I have no experience with body work.