Our 13B vs New 13B
 

What are the main differences between say my 86 4 port 13B and the twin turbo 13B block? Can i get turbo stuff and intake/ exhaust manifolds that are for a 93+ and fit them without trouble?

No. Intake port configuration is different. The REW is a pita, the TII is a much better choice. The only way you can have an 86 4-port is if it is a JDM TII import. There were no USDM 4-port 13Bs.

All turbos are 4 port.

Exactly, from 86 on and the US market didn't get them until 87.

Old 13Bs (read REPUs, etc.) had 13B 4 ports, and they were not turbo. What are you talking about trochoid?

*Edit* Nevermind. I thought you meant that 4 port 13bs were non-existant (period) in the US before 1987. When, in fact, you meant only turbo motors. My bad.

LOL. I just bought an engineless REPU, I know about the 74-78 13Bs.