what would need to be done to fit these on my 89 GTA?

i know that the offset will be the only problem correct? I wouldnt have to trim the bolt holes larger would I? I believe they are 5 x 120 and ours are 5 x 120.65 but i know that 4th gens are 5 x 120 and their rims fit just fine on ours besides the offset

well, i know that the GTAs suspension can be a problem bc once a tire shop accid put my rear rim on the front 16mm offset as opposed to 0 offset and it rubbed against my tie rod end...would this clear since its an 18 inch rim? I know that i would need a spacer what size? 1 inch 1.25inch?

any advice or info would be GREATLY appreciated

 

here are my calculations let me know if incorrect

two 1.30" thick adapters would bring the wheel offset from 35mm to 1.98mm for the front

two 1" thick adapters would bring the wheel offset from 35mm to
9.6mm for the rears

should this setup work as long as the 5 X 120 pattern will fit on my lug setup?

CALCULATIONS for those who want to know how
1"=25.4mm
1" and 1.3" = adapter thickness (adapters are safer than spacers)
35mm = the offset of wanted wheels

25.4mm*1.3"=33.02mm-35mm=1.98mm
25.4mm*1"=25.4mm-35mm=9.6mm

 

ttt

 

can someone plz give me a quick answer to this question? i know its tedius but surely someone can tell me

 

ive kinda redone my calculations bc i realized that im changing the backspacing rather than calculating a difference in actual mm offset

so heres what i got
on the 18X8.5 wheels i got a 5.63" backspacing
on the 18X9.5 wheels i got a 6.13" backspacing

with a 1.5" adapter on the fronts and rears i come to 4.13" backspacing closest i could get to original 4" backspacing for the fronts and 4.63" PERFECT match to the original stock rear gta wheel offset...so it should be extremely close to exactly how my GTA golds fit

 

if they are made for a 4th gen, you'll need 2" adapters.

 

no offense at all but why is that? the bolt pattern will fit a fourth gen, the rest of the wheels actual dimensions dont change just because its made for a fourth gen...unless your thinking that im talking about actual fourth gen wheels

 

4th gens have 4" extra width on the axle and front spinles so if the wheel is made for a 4th gen you will need to make up that 4" of diference with a 2" spacer on each wheel. this applys to any wheel made for a 4th gen origional or aftermarket. the bolt pattern and all that are the same as a thirdgen but it has an extra 2" of backspacing on each wheel.

 

so what do i need to do if i get 4th gens? get a 2"thick adapter + the already 1.5" adapter to correct the backspacing or is it just 2" thick all together?

also what about if i get the same wheel built for BMWs with 5x120..and adapters and such?

 

also wouldnt the offset change? like if they made them for a bmw with a 35mm offset and then made them for a 4th gen that has a wider rear axle why would they make them to the exact same specifications?

just wondering i understand what your saying about the rear axle of the 4th gens but i still dont get it bc the geometry of the wheels are still the same

 

I've looked at BMW wheels before, and I like the look. However, I don't like the idea of the fitment not being dead on. I don't believe the 4th gen wheels are 5x120 either. You might want to relook that up.

 

yeah i checked and they are the same pattern as 3rd gens 5X4.75 which is fine but ill be using 100% safe adapters i can chose almost ANY lug pattern 4 lug 5 lug or even 6 lug (no way but just ie)...and it will sit on my axle safely i talked to my boss today...i work at discount tire...and we both agreed that the math is correct and i should only need 1.5" spacers bc the fact that the 4th gen axle is 2"wider on each side does not change the actual dimensions of these wheels

so i guess ive got it all figured out and ill have some pics of the wheels in a couple months once ive bought them painted my car had it lowered and them FINALLY installed...haha