13B EFI from GSL-SE into earlier RX-7, who's done it?
 

So I'm tring to gather all the resources I need to swap over a 13B EFI from a GSL-SE into my '79 SA. I want to retain the stock fuel injection for cost reasons and haven't found much in the archives on people who have done this swap with the EFI intact. Does anyone have any tips, pointers or resources they could throw my way? I'm fairly lucky in that I have an entire engine bay to get parts from, I'm not just contending with the engine, so if I need any bits and pieces from the enginebay of the SE, I can get them.

So how 'bout it people, what have you done in order to retain EFI while swapping engines to non-EFI RX-7's?

Hey man im doing this same thing right now, i started a thread a couple days ago.
From what i've gathered, you need to replace the old ecu with the se one. You will need to do your own wiring layout for a few components. You should put the se fuel tank on the older car with hard fuel lines.

I think that is most of it, but i am still trying to figure this out too.

You got it made in the shade with that swap.....

Since both cars are 1st gens,its almost just remove and replace.First,strip the SA's engine bay bare except for the chassis harness and non-engine related parts.Everything from under the SE's hood should be able to fit in roughly the same place under the SA's hood.The wiring should be about the same as with FC engine swaps,meaning that 75%-85% of the EFI wiring is plug and play between the engine and ECU on the passengers side.The remaining wires will go from the ECU to the left side of the engine bay,powering the ECU,coils,distributor and fuel pump........of course,the 12A style ignition system of the SE engine might mean that powering your coils and distributor will be a simple 1st gen style wiring job.The SE's ECU isnt even in the loop for ignition,so left side engine wiring should be even simpler than it was for my swaps.
Get an FC underhood fuse block.Its way better than the fusible links and itll have sockets for the ECU power relay and a few extra accesories.

The SE fuel tank wont fit in the SA chassis,so youll have to get creative with the fuel delivery system.Obviously,its easy enough to mount the SE's external EFI style pump,but youll need some sort of slosh baffle in the tank to prevent pressure loss when the tank is below 1/2 and you are turning.Not to hard a job,but custom fab work none the less....

The torque monster SE engine in a light,sparten SA chassis.....sounds like fun.

An alternative to the slosh baffle that is in the SE tank, is installing a surge tank. I recommend swaping the to the SE fuel lines too, as they are bigger than all of the 12A ones. You don't need to switch the return line, unless the SA one is smaller than the FB one. The SE return line is the same diameter as the FB supply, the SE supply line is one size up. By using the SE supply, you can mount the FI fuel filter in the stock location.

All of the rubber fuel HAVE to be replaced with FI rated fuel lines and the matching FI hose clamps. The line between the tank and pump can be carb rated, but you should add a high flow fuel filter, pre-pump, as I don't think the SA tanks have an internal filter screen on the pickup tube.

I installed the SE tank in my SA... what I did was cut out the spare well, shortened it about an inch and a half, and welded it back in. At that point it fit.

Thanks for the tips guys!

I'm starting engine removal and bay cleaning next week, at which point I'm sure I'll be back with more questions.

me not wanting to start a new thread id rather bring this one back i started this project and im gettin alil lost i prnted out all the wiring diagrams and there are a few things that i cant find and im not 100% sure on yet. so here it goes.

1 in red is this the control unit?if this isnt the control unit what is it and do i need it?

2 in green this goes to the engine harness loom and it runs all the way to the driver side and i cant find this in the wiring digrams what is it all for.

3 i pulld the dash in the 85 SE the i got this from and i know that some of the wires go to the intumnet panel and go the the engine bay and go to the the driver side and then travel downwards with the speakerwires. thats all i know at this point. i did go out and get a 2nd gen engine fuse box thingy.

4 all the relay looking things up in the driver side of the engine bay near the window do i need to get those too im going to be using the cruise control i just want the engine and ecu.

i know that this is a lot but there isnt much out there for the GSL-SE engine swaps out there!

bump

You need a couple of frame parts from the GSL-SE as well. See this:
http://mrmazda.no-ip.com/cartech.html#12A-2-13B

thank you,but i really need for the wiring

Heh, my own project stalled due to lack of funds.

Do you have the factory wiring diagrams for the '85? If not, you can download them at www.wankel.net/~krwright

i got them but i dont quite understand them

There should be a color key which tells you what the various abbreviations mean. After that, it's just a matter of tracing the lines.

Using my experience with 2nd gen EFI,Id say that the black box you have circled in red is the circuit opening relay.Its basically the relay that operates the fuel pump.
Directly to the left and below the circuit opening relay,is the barometric sensor,whcih tells the ECU the outside air pressure.
To the left of that, is the relief solenoid control unit.Its part of the air injection system(smog gear).Using input from the floor temp sender and that control box,the relief valve shuts off air to the cats when they get too hot,preventing meltdown and a potential fire.
It looks like those 3 items are wired into the dashboard harness(similar to 2nd gens).Youll have to get a full wiring diagram to get it all figured out.This is similar to the custom left side wiring that is required when swapping in a 2nd gen engine.This entails wiring up the ECU main relay near the left strut tower and poviding power to the ECU and fuel pump.Since the distributor and coils are not ECU controled on the SE,they will likely not need any attention,unlike the FC swap.

how hard do you guys think this would be to do to an rx-4?

where can i get a full wiring diagram from. the one im using now is from the fsm and the only place i can find the plug circled in green is on the last page and its just the connector?

There's a full '84 diagram on that site. I don't think that much changed between the two years...