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Discussion Starter · #1 ·
Total Newbie Question here...thanks for suffering.
I have a 1970 Pontiac GT37/GTO, it has the typical 5 bolt/nut pattern on the wheels---will all 5 bolt/nut pattern wheels fit my pattern? Or is it much more detailed than that? Thanks
 

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Old(s) Fart
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In a word....yes.
Wheel sizing - Wikipedia, the free encyclopedia
Pay particular attention to "centerbore". Matching this will take the radial load off the studs/nuts.
That seems to be a euro-centric Wiki entry. Suffice to say that your Pontiac uses the 5 x 4.75" wheel bolt circle that's probably THE most common one for aftermarket wheels. I will guarantee, however, that if you DON'T verify the bolt pattern before buying wheels, you'll get the wrong one.

Also, your RWD car wants wheels with as close to zero offset as possible. That means you cannot use the FWD wheels that have a large positive offset. Offset is the measurement of how far the wheel mounting surface is "offset" from the centerline of the rim. Zero offset means that they are lined up. Positive offset means that the rim (and tire) centerline is further inboard than the wheel mounting surface, negative offset means that it is outboard. Unfortunately, most wheel vendors specify backspacing instead of offset, and that's not really useful without also knowing the wheel width and the additional flange thickness on the edges of the rim.
 

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WFO
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Total Newbie Question here...thanks for suffering.
I have a 1970 Pontiac GT37/GTO, it has the typical 5 bolt/nut pattern on the wheels---will all 5 bolt/nut pattern wheels fit my pattern? Or is it much more detailed than that? Thanks
Here you go. You'll be looking for the 5 on 4-3/4" pattern wheels. There's more to it than just the wheel bolt pattern, things to look for are covered there.

Good luck.
 

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Discussion Starter · #5 ·
This is great information-thanks so much!
Where did you look up my wheels being 5x4.75? I have been looking everywhere for that information and couldn't find it anywhere.
 

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Old(s) Fart
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This is great information-thanks so much!
Where did you look up my wheels being 5x4.75? I have been looking everywhere for that information and couldn't find it anywhere.
Every GM RWD intermediate (Chevelle, LeMans, Cutlass, Skylark) built from 1964 to 1988 used the 5 x 4.75 pattern.
 

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wrong center bore

My son used a mustang steel spare wheel for his spare on a Lincoln Versailles 9 in rear. He went from N Calif bay area to LA, with the mustang wheel, He was " too busy" to get the correct aluminum wheel flat fixed. Some where in the middle of an LA freeway the wheel started to wobble. IT had several cracks. Lucky, the traffic jam had traffic only going 25 mph.
 

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My son used a mustang steel spare wheel for his spare on a Lincoln Versailles 9 in rear. He went from N Calif bay area to LA, with the mustang wheel, He was " too busy" to get the correct aluminum wheel flat fixed. Some where in the middle of an LA freeway the wheel started to wobble. IT had several cracks. Lucky, the traffic jam had traffic only going 25 mph.
The mustang has a 4.5 x 5 bolt pattern the linclon 85 or newer have a 114 mm x 5 it will bolt on But will not stay tight when you start to drive.:(
 

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WFO
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My son used a mustang steel spare wheel for his spare on a Lincoln Versailles 9 in rear. He went from N Calif bay area to LA, with the mustang wheel, He was " too busy" to get the correct aluminum wheel flat fixed. Some where in the middle of an LA freeway the wheel started to wobble. IT had several cracks. Lucky, the traffic jam had traffic only going 25 mph.
In theory if the centerbore is too large this can happen as well.
 

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WFO
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According to the VIN it is a GT-37 :)
Nice find. Not to disillusion you but it would prollably be more accurate to call your '70 a GT-37/Tempest. One main reason for its existence was to not be as "sporty" as the GTO (bench seats, stripped down) so it could be insured cheaper. That actually made it quicker than a lot of GTOs, though.;)
 

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Discussion Starter · #13 ·
That's great! I would go a step further and call it a Frankenstein GTO/37...someone really hacked into it at some point wanting a GTO- they put on the GTO Hood, Endura front bumper, rear wing, and full GTO interior with buckets. I am still trying to figure out the engine, I am having a hard time finding the stamp on the block, I did find an "XS"...it has an edlebrock manifold into a rochester carb.
 

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mustang wheel.

the 9 in disc rear was out of a mid 70's. versailles. the mustamg center hole was a little bit smaller, but the bolt pattern was the same.the wheel lug area did not fit tight to the rotor.
 

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According to the VIN it is a GT-37 :)
Your serial # should ba 233370 a or p 1xxxxxxx1 ,the first 2 means pontiac division of gm next 33 is body style T37 the 37 means 2 dr ht 0 yr 1970 1xxxxx1 production # trere were only 1413 produced in 1970 so you have a rare car if is a pillow post car it will have a different # even more rare ut is a version like the 300 series Chevelle ,it was designed as a light weight low cost car to compete with Roadrunner and Superbee it will have a 400 Only engine offered,a overhead cam 6 a 326 ,350 and 400 were offered in a lemans ,same car just up scale 70 t37 were tempest 71 were lemans or tempest depending on if it was a hardtop or post ,this car has value,check it out,If tou want i will decode it for yor list First part of data plate DO NOT list serial #on here,uf early 70 data plate will be in windsheild later 70 is on firewall above brake boosterm Hope this helps
 
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