Corvette C4 wheels go or no go? - New Caprice (2024)

Suggested reading: https://www.ssforums.com/forum/discount ... ost3495561

Bill Harper
inov8r@windstream.net

the early C4's were a different offset than the later C4's from my understanding

BUT

since you have them , its easier for you to try them out and see

Navy Lifer wrote: ↑Wed Jan 23, 2019 9:41 pmSuggested reading: https://www.ssforums.com/forum/discount ... ost3495561

I have seen threads like that but no one comes down to saying if you can run 120 wheels on a 120.65 pattern.

s/c'd cav wrote: ↑Thu Jan 24, 2019 9:56 amthe early C4's were a different offset than the later C4's from my understanding

BUT

since you have them , its easier for you to try them out and see

that was my plan.....if it ever gets about 10 degrees here

jj55chevy wrote: ↑Fri Jan 25, 2019 2:15 pm

Navy Lifer wrote: ↑Wed Jan 23, 2019 9:41 pmSuggested reading: https://www.ssforums.com/forum/discount ... ost3495561

I have seen threads like that but no one comes down to saying if you can run 120 wheels on a 120.65 pattern.

Let me help....culled from the original link posted by Discount Tire: "Remember, your vehicle will only accept a wheel with the same bolt pattern as the original equipment wheel."

Obviously, some don't agree with this, but, while it may not say specifically that "you can't", the intent is to make it understood that proper fitment is achieved using components that match. 120mm & 120.65mm are not a match, and I assure you that GM would not bless mixing them on a vehicle designed for either PCD (ie. stud pattern).

Your original question was one of "would (the C4 wheels) fit" - and in a loose definition, yes, they will fit, but not in the manner they were designed and intended. I refer back to the quote above.

Bill Harper
inov8r@windstream.net

Navy Lifer wrote: ↑Fri Jan 25, 2019 4:15 pm

jj55chevy wrote: ↑Fri Jan 25, 2019 2:15 pm

Navy Lifer wrote: ↑Wed Jan 23, 2019 9:41 pmSuggested reading: https://www.ssforums.com/forum/discount ... ost3495561

I have seen threads like that but no one comes down to saying if you can run 120 wheels on a 120.65 pattern.

Let me help....culled from the original link posted by Discount Tire: "Remember, your vehicle will only accept a wheel with the same bolt pattern as the original equipment wheel."

Obviously, some don't agree with this, but, while it may not say specifically that "you can't", the intent is to make it understood that proper fitment is achieved using components that match. 120mm & 120.65mm are not a match, and I assure you that GM would not bless mixing them on a vehicle designed for either PCD (ie. stud pattern).

Your original question was one of "would (the C4 wheels) fit" - and in a loose definition, yes, they will fit, but not in the manner they were designed and intended. I refer back to the quote above.

I'll take that as the final answer!! I will just buy new rims in the spring, thanks!!!

jj55chevy wrote: ↑Fri Jan 25, 2019 2:15 pm

Navy Lifer wrote: ↑Wed Jan 23, 2019 9:41 pmSuggested reading: https://www.ssforums.com/forum/discount ... ost3495561

I have seen threads like that but no one comes down to saying if you can run 120 wheels on a 120.65 pattern.

Allow me a clarification--the exact wording of your statement does matter, assuming you are referring to OE GM wheels.

Wheels for fitment to 120mm PCD have a wheel center bore of about 67mm

Wheels for fitment to 120.65mm PCD have a wheel center bore of 70.3 to 70.5mm (depends on model year)

Since the center bore on 120.65 wheels is larger, it is possible to "mount" wheels with this PCD on a vehicle with 120mm PCD. There is no hub-centric function on the hub register, and wheel studs are side loaded when torqued, and lug-nut taper contact on the seating surfaces of the wheel are not correct.

Wheels of the 120mm PCD, with the smaller center bore, will not physically fit on a 120.65 hub, since the hub register is too large to allow a 120mm wheel to physically seat against the rotor/hub flange.

Bill Harper
inov8r@windstream.net

id be more worried about the offset of the wheels working , plus the hub bore

the slight difference in the 120 vs 120.65 lug pattern , is correctable , they do offer lug nuts that have the conical seats loose on the nut , and they can make up a few MM of lug pattern difference

will the 120 or 120.65 patterns bolt together as is , yes BUT , its not 100% it can stress the studs , and/or conical seat wont sit correctly in the wheel , slotted mag style wheels that use a shank will bolt up more correctly than a conical in this instance

so in the end its do which you feel comfortable with