12a Turbo
 

Well, just bought a 12a turbo from Japan2La. I don't know much about the engines so I am looking on advice from someone who has worked with them.
I am thinking about going with a Megasquirt II EFI kit.

Anything I need to know so I can have my car ready to install it when it gets here?

I've got a totally stock '85 GS.

Thanks,
Dylan

G/L with it post pics up when you have time, Japan2LA is a good seller.



Trini

Thanks, I will definitely get pics up as I progress. Going to be working in the winter, luckily I have a heated garage.



Planning on bolting it onto my 12A transmission, will it take the turbo?

12a trans will not take the abuse if you hook up.

A TII Trans would work right?

Yes, a TII transmission will work for what you want to do. It will take some minor modifications to get it in there but it will work. Do a search in the 1st Gen forum on TII Transmission and you will pull up at least one thread on how to get it done. Good luck!

You can blow any transmission with stock 12a power. The question is how hard you are on it.

Bad 83 ran a turbo'd 12a with 15psi on the stock trans. Never blew out.

Thats what I was looking for ;) Right now I just need a running car, not looking to do any major upgrades until summer comes along.

the stock 12A-T ecu is similar to the gsl-se, except it has TWO ecu's. one emissions control box like the us spec 12a, and one ecu like the gsl-se.

megasquirt would probably be easier than hooking up the 12AT ecu's provided you get them. next would be a gsl-se ecu/harness...

Yep, it isn't coming with the ECU's I believe, so my first choice was megasquirt. Need a harness though.

12a turbo
 

i just installed 12a jdm turbo in my racecar.i changed the efi and is running a 600 holley blow thur set up. make sure it come with the dist.

The easiest way to do this, is to run a TII CAS, and let the Megasquirt handle both ignition and fuel. I have one of these engines myself, running a stock 12AT tranny, and it handles 500 RWHP no problem. If the tranny does not come with the engine, run a TII, it will handle way more than the stock 12AT.

Also, if you are planning on running more boost than stock, get a front mount intercooler..

I have a volvo FMIC at the moment. An OEM 12A transmission won't work? Because I don't have a 12at tranny

12a turbo
 

would a measquirt ms122-c w/pcb2.2 work. for fuel or both fuel and ignition. you can email me at sonnytalfred@yahoo.com

So I could use the ecu and harness from a gsl-se?

it plugs into the engine BUT its not going to "see" boost, so you need to be careful

Would a harness from a turbo 13b work? Just trying to find out something that I could buy instead of a 12AT harness, because no one seems to have one :P

I think FI would technically work best, but it sounds like you are going for simple easy and effective... In that case, I think a nice boost prepped carb and rising rate fuel pressure regulator would work nicely.

no. the 12A-T and GSL-SE share most of their (weird) sensors.

if you had to run some other stock ecu, you'd have to swap out a bunch of stuff on the engine

Just get a microtech lt8 :nod:

Yeah looking that way. I was just trying to see if there was anything I could get quickly. Thanks guys, I'll be posting some pics soon.

If anyone could point me in the direction of a site with 12AT harnesses please PM me. lol

When you get the 12a Turbo can you post lots of pictures of it from different angles? It's a rare engine... I've seen more 20B's than 12a T's

I wouldn't recommend a Megasquirt unless you already have experience with wiring and tuning standalones. It has less support than the other options.

I'll take pictures of whatever you guys ask. Rx7club has helped me enough, I think I should return the favor :P

I'm not sure if you were planning on pulling most of the stuff off the motor for cleaning/inspection, but I would love to see good quality shots the stuff in this area:

https://www.rx7club.com/attachment.p...1&d=1260803696

I like to study OEM designs, I think they teach you a lot about cars. I've been studying the Turbo II and the FD a lot. I am VERY curious about this 12a T because I think it can teach us a lot about the evolution of the rotary since Mazda built on these designs. It's just like how you can see a lot of the GSL-SE designs in the Rx-8 today.

I've got a gazillion questions in my head that I don't expect to be fully answered. Things I'm interested in on your motor:

The thing in red I'm guessing is the intake manifold. I'd live to see the inlet and outlet of this piece. The engine is not intercooled. What does the LIM look like? How is oil and coolant routed for the turbo, do they connect to the front cover? Is the turbo even water cooled?

This is a fuel injected car right? What does the fuel rail look like... are the injectors really the same as the light blue Greddy 720cc's ? I heard a rumor that Greddy resells 12aT injectors, they are 720cc low impedence. I have those 720's in the primary position of my T2 right now.

What does the exhaust manifold look like? Mazda changed the exhaust manifold in the Turbo II's, series 4 and series 5 differ.

Are there any markings on the turbo that would indicate the model number? The Turbo II used an HT18, the Cosmo 13B-RE used twin HT10's, the FD REW used twin HT12's, the Cosmo 20B used one HT15 and one HT10. What are the sizes of the wheels on the turbo, both inducer and exducer on compressor and turbine wheels? What does the wastegate look like and what size

Where is the throttlebody positioned... It looks like it's downdraft style? Does it have a large primary throttle plate and then two secondary throttle plates, just like the EFI 13B throttlebodies? Does this car have a GSL-SE style BAC valve (vacuum orifice thingie) or an actual solenoid valve like the later cars?

I would LOVE to see detailed pics of a lot of the components, but even some clear pics of the longblock would be nice.