I have a 1985 GSL-SE with a TII Swap and I am looking at maybe getting some new rims. They are 13x6 with a 3.75" backspace. They have the right bolt pattern.

 

1) I don't know crap.
2) I think 3.75" = 95.25mm. Is backspace the inside or outside?
3) I read that a GSL SE requires roughly a 35-40mm offset.
4) I am probably way off. =)

The 13x6 is fine I'm sure.

 

He also referred to it as a 6mm postive offset, whatever that means. Is going to a smaller rim a good idea? I mean, I know you get less unsprung weight, but having a 260hp Turbo engine on 13's might not be the ideal solution.

 

They'll fit.. . but they're not really ideal.. I run 13x8" w/ 4" backsapce for autoX on my SE...

Go wider!

 

What is the factory offset for the GSL-SE?

I'm looking at some Rota RB's in 15 x7 and 15 x 8 for the rear. Vendor says they have a +12 mm offset.

Should these fit? Will they give it a nice, wide stance in the rear? I want some rear fender flares, and I need some wheels that will fill them out pretty good.

 

I believe it's 40mm positive offset. I belive that works out to 4.1" backspacing.

 

Do you know how wide the factory wheel is? 6"?

 

14x5.5 is the size of the oem rims on our gsl-se we have in the shop waiting a t2 swap.

 

smaller rim = faster acceleration, due to lower gearing. It will depend on the sidewall height of your tires of course.