rims - 2nd gen
 

hi i have a 86 gxl "base model" wondering what the 4 bolt patern is on it. and how big of a rim i can go also profile of tire.. Also i have a 89 donor car with 5 bolt can i just switch out hub assembly and brakes for my 86 ?? or do i have to put whole front rack in ?? thanks james

The pattern is 4x114.3 mm.

I'll let someone else answer the other questions as I am more of a 1st gen guy.

There is a huge wheel thread here https://www.rx7club.com/suspension-wheels-tires-brakes-20/official-fc-wheel-fitment-thread-257700/.
Hubs and brakes will swap over without the crossmember. Hopefully your donor car has the 4-piston brakes since you're there.