Need to change wheel studs when using adapters??
Thread Starter
Instructor
Joined: Apr 2005
Posts: 129
Likes: 0
From: Charleston SC
Need to change wheel studs when using adapters??
Just got off the phone with Group A wheels whom I've dealt with before and had great results on the "very hard to fit aftermarket wheels on 2004 GTO". Anyway, I want to fit some modern style 18 x 8 and 18x9 rims on my 1973 coupe. So they stated that their wheels should fit fine if I used their 1 inch adapter- easy enough. But then stated that the manufacturer required that the stock 7/16 wheel studs be changed to 1/2 inch or 12mm for added strength with the adapters in place.... Anyone else heard of this problem?? I thought plenty of folks around here used adapters, and I don't recall anyone stating that they changed the studs. I assume that this would be a real pain in the ***, especially on the rear... Any input is appreciated! 
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Okay, using the thicker studs is only needed if the wheel adapters are NOT hub centric. This means the inside opening of the adapter perfectly slides over the lip on the hub, which actually supports the weight on the wheels.
If the opening in the center of the adapter is larger than the lip, it's 'safer' to install larger studs to help support the weight of the car. The studs are more likely to bend or break during aggressive driving if they are not upgraded.
Being that they are only 1" studs you're better off than if they were 2.75" adapters or something obscene.
The swap is difficult for the rear wheels for sure but the fronts is a bit easier. You'll need a centering jig to drill the stud holes out perfectly. The rears are tough because you have to disassemble the trailing arms to get the jig and studs in the flange. The front hub is fairly easy to get off.
If the opening in the center of the adapter is larger than the lip, it's 'safer' to install larger studs to help support the weight of the car. The studs are more likely to bend or break during aggressive driving if they are not upgraded.
Being that they are only 1" studs you're better off than if they were 2.75" adapters or something obscene.
The swap is difficult for the rear wheels for sure but the fronts is a bit easier. You'll need a centering jig to drill the stud holes out perfectly. The rears are tough because you have to disassemble the trailing arms to get the jig and studs in the flange. The front hub is fairly easy to get off.
Thread Starter
Instructor
Joined: Apr 2005
Posts: 129
Likes: 0
From: Charleston SC
Okay, using the thicker studs is only needed if the wheel adapters are NOT hub centric. This means the inside opening of the adapter perfectly slides over the lip on the hub, which actually supports the weight on the wheels.
If the opening in the center of the adapter is larger than the lip, it's 'safer' to install larger studs to help support the weight of the car. The studs are more likely to bend or break during aggressive driving if they are not upgraded.
Being that they are only 1" studs you're better off than if they were 2.75" adapters or something obscene.
The swap is difficult for the rear wheels for sure but the fronts is a bit easier. You'll need a centering jig to drill the stud holes out perfectly. The rears are tough because you have to disassemble the trailing arms to get the jig and studs in the flange. The front hub is fairly easy to get off.
If the opening in the center of the adapter is larger than the lip, it's 'safer' to install larger studs to help support the weight of the car. The studs are more likely to bend or break during aggressive driving if they are not upgraded.
Being that they are only 1" studs you're better off than if they were 2.75" adapters or something obscene.
The swap is difficult for the rear wheels for sure but the fronts is a bit easier. You'll need a centering jig to drill the stud holes out perfectly. The rears are tough because you have to disassemble the trailing arms to get the jig and studs in the flange. The front hub is fairly easy to get off.
Thanks for the reply, I figured that it was just a CYA move. I'm not going to autocross or anything, just crusing with the occasional straight line blast. Also, of note, they stated that the 1" adapters would be custom machined- and would be hub centric to the wheel and original hub. I think I would be ok with not changing the studs.....
Any other opinions??
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Thanks for the reply, I figured that it was just a CYA move. I'm not going to autocross or anything, just crusing with the occasional straight line blast. Also, of note, they stated that the 1" adapters would be custom machined- and would be hub centric to the wheel and original hub. I think I would be ok with not changing the studs.....
Any other opinions??
Any other opinions??
If the adapters ARE hub centric then you don't need to upgrade the studs.
