I just recently bought some Weld Prostars 15x3.5 Fronts and 15x8 Rears. The person I bought them from had 3/8" spacers with them. So I bolted them on the other day, and heard a grinding noise, like something was rubbing metal to metal. So I took off the back wheels, and the brake caliper was rubbing on the inside of the wheel. So just messing around, I put two 3/8" spacers on there to see if that would fix the problem. Well, it doesn't rub, but now the lug nuts won't bolt on. What will fix my problem and where can I find it. Thanks for the help in advance.

 

ARP longer studs PN 100-7708.

 

Grind the fin's on the caliper's to clear if the back space is right.If 3/8" makes the lug nuts not go on ya need longer studs or get grade 8 bolts and tap the axle and install them with the heads to the back and use them for studs. Nothing less than grade 8 which is 6 lines on the head. Longer studs are easier.

 

The 3/8 spacers are enough to where the lugnuts can go on. Its when I put 2 3/8 spacers the lugnuts will not go on. So I'm going to try to grind down the calipers a little bit.

 

A few items.....

1. Wheel questions belong on "Wheels and Tires" forum, not on LT1 Engine Tech. I'll move it there.

2. I know I've answered this question and posted links to pictures of the caliper grinding many times. A "search" should have turned up those posts.

Do not use spacers in the back, particularly not stacked spacers. You will run the risk of shearing the studs right off. If you grind the calipers, you will not need any spacers.

In the front, you will need a spacer. Most people use 5/16", not 3/8". You will need longer studs to pass NHRA tech. The studs must engage a full 1/2" of the threads in the "hex" portion of the lug. NHRA will not give you any credit for the threads that engage the shank portion of the lugs.