I have a 12A in my 1980 RX. I am looking for a 13B turbo. Couple questions. do those engines just fall in and mount up? and where can i look to find one in good condition. if not should i rebuild it and port it out to get more performance. someone help me here. thanks

 

all the answers are here: https://www.rx7club.com/1st-generation-specific-1979-1985-18/1st-gen-rx-7-faq-page-237777/

 

If you happen to have a healthy 13B turbo engine already,theres no need to tear it down just for porting.It will make a small improvement in power,but forced induction can make massive power on stock TII ports just fine.
The 13BT will bolt right into any 1st gen chassis.To get the mounting down youll need.............
GSL-SE oilpan.
GSL-SE front cover.(to retain the S4 oil metering pump,or use any 1st gen front cover if you run premix)
GSL-SE front mount bar and right motor mount.(or bend,grind the 12A front bar)

Thats all you need to get mounted up.There is obviously a LOT more involved to getting it running and reliable,but you only asked about mounting!
13BT's can be found all over.Ebay,PartsTrader,FC sites,ect.....Some private party,some imported low milage J-specs.

 

yea don't port it unless it just needs the rebuild. people here are getting over 400rwhp on stock port S4 tII blocks. daily drivers baby! i still HEART my 12a

 

thanks for all the info so far. well mounting it doesn't seem all that hard so tell me about getting it to run. is it alot of work and rewiring?

 

*ahem*

 

Bolts right in!

 

The 13bs bolt right in?

 

For the most part,yes.
The GSL-SE came factory 13B equipped,so physically mounting a 13B in the 1st gen chassis isnt too hard.
Getting all the EFI and ancillaries working is another case.Its a job,but not too complicated if your familiar with the engine.

 

If you can't read a wiring diagram you'll need to learn quick.

If you have the money go stand-alone instead of using the stock computer. It's much much easier than building a custom harness out of the front harness and mating it to the emissions harness

 

For the record,theres no mating or splicing required when fabricating the left FC engine harness.
The bulk of the EFI wiring is on the right side,plug and play from the engine to the ECU in 2 large gang plugs.
The 3rd, left hand harness consists of about 12-15 wires powering the coils,fuel pump,ECU power relay and CAS(S4).
Using an FC fuse box and main relay,the harness goes directly from the FC components into the ECU.Its very direct and simple with zero intrusions into the FB's power or accesory harness'.

 

Can I run a carburated 13bt

 

Yea,but itd be more work since you have to adapt the carb to run boost and youll have to pitch all the intake manifolds and fabricate new piping and a hat.And youll have to plug the injector ports in the center plate.And youll have to tune the carb on the engine.And itll NEVER be smog legal.
If your absolutely allergic to wiring,you can go carb.But if you already have all the pieces to make the FC EFI work,itd be a shame to pass on the increased power,driveabilty and economy that EFI offers.The FC ECU is pretuned,ready to run from 250-300HP with the right mods.