Ammoz85

85 GSL-SE with 13b. Not sure if its the original engine or not so don't know if it's even from an 85. Wanted to know how to determine if it is a 4 port or 6 port? Or are all 13b's 6 port? Thanks

OG BBF

85 GSL-SE from factory came with the 13b engine. The others were 12a. I believe the 13b in yours should be 6 port as they came 4 port in the later turbo 2 models.

If your car is N/A with 13b I'll bet my house it's a 6port original

Ammoz85

Thank you OG BBF, Yes my current set up is that 13b (street port) with a Demon 850 carb, MSD ignition, full RB exhaust (Header back), AC delete, AEM air/fuel sensor and upgraded alternator. I figured it had to be a 6 port. Know the 12a are 4 ports but thought I read somewhere that some 13b's have only 4 as well.
Current electrical wiring is suspect to say the least. Previous owner was sloppy with it after converting from Fuel Injection to NA so will be rewiring engine compartment to help prevent issues and for a more clean look. Looking for a complete engine compartment wiring harness but may just do it wire by wire! Since it's NA now would a harness from a 12a help? Also any idea if a FC manual transmission will fit and work with my set up?
Cheers!

OG BBF

Sounds like a nice promising setup, cars this age will always need some sort of tlc but it's well worth it. If you have the patience I would go wire by wire rewire but it's a hell of a lot of work.

Yeah the 13b went 4 port when Mazda decided to go turbo on the FC model. As far as using an FC tranny on your engine it can be done however it's not a straight bolt on. When the TII 13b was released Mazda made the transmission housing larger to fit a larger flywheel and also starter I believe is in a different location. The NA FC3S tranny however maybe easier....only design change was the mount location. What is the difference between your tranny and the FC NA one? I don't know, perhaps someone with a little more experience in these swaps will chime in. Or drop mazdatrix an email, they have done quite a few swaps in the past.

With regards to the 12a harness I couldn't say, I don't know. Logically I would think so, or maybe a 13b na harness modified. But couldn't say for sure. Sorry.

Ammoz85

Ok Thanks again for your feedback especially in regards to the tranny. Start on the wiring next weekend. It should be interesting. I'll take some pre and post pictures to share.

rxtasy3

iTrader: (2)

early 13b(pre 79) were 4 port also. FC trans will bolt to the engine, problem would be shifter location and maybe the mounting location as well. never delt with fc's so not really sure.