13b re cosmo in Rx3
 

O.k. here's the deal

I have bought a 93 cosmo front clip.
It includes everything from the tailshaft on the automatic trans to the front bumper.
I would like to install the stock motor in a 74 rx3, but i have to go single turbo as the TT set up doesn't fit. I don't think i need more than 10-12psi of boost.

Questions?

1. Can i use the stock ecu (automatic trans & Twin Turbo) ?. I have T2 5spd trans, flywheel, front cover and counter weight.

2. Turbo & ECU recomendations ?

Any help will be greatly appreciated.

Thanks,
Rick

Here's the chosen one.

Rick, I would strongly suggest making the stock twin turbo set up fit. Nothing a welder and cutting torch cant fix assuming its a clearance issue. If this is beyond your skills consider having it done,any welding shop can notch the frame rail and reinforce it. The reason why Im suggesting this are many. Its a lot easier to mod whatever is keeping the stock turbos from fitting than to start swapping parts and then end up with a tuning nightmare. Dont be afraid to cut away steel and weld in new,a engine bay is easy to repaint. Also a custom turbo manifold may solve your problems as well. Since you have a complete front clip I would swap over everything and keep it stock. That way you keep the reliability. Just keep it simple and get it running...then you can perform any modifications if you want. DO NOT modify the engine while its out of the car and access is easy. Later when it isnt running right youll have no idea what to troubleshoot first. And any experienced professional mechanic would be lost as well. Wish you luck.

I have that engine in my 74 Rx2 but I went single T66. It also has a haltech e6x not that hard to tune this is my first stand alone ecu. There is a guy on the forum who has a 20B in a 616 that makes turbo manifolds for about $250. I will find his site and post for you.

I would still stick with the stock ecu and harness and at least get it running that way. If you decide to upgrade to a stand alone you can then do that at any time. Basic idea is to swap the engine get it running and then do upgrades. Trying to do it all at once makes things more complicated. Maybe Im just getting old..lol. You do what works for you.

Thanks for the replys.

I would like to avoid cutting any part of my car as much as possible.
although i'm sure that can't be avoided.

Can i use the T2 trans set up with the stock ECU ?
In other words can you take an automatic FD and convert it to a Manual FD using the automatics stock ECU.

Thanks again
Rick

sorry you can't use the Stock ecu and wiring..

the stock ecu is connected to the "tv" in the dash as well as the Tranny...

the ecu will check for these.. and when they are missing it will take a shit and go into limp mode...

i've heard of someone in Aus. using resistors to trick the ecu into thinking the missing components were there... but it's a real pain in the ass... and the stock Ecu sux.. (u want a auto rev limiter?)

ur other cheap alternative is to try and use a Turbo II wiring and ecu

they both use the same size injectors.. and are similar motors

of course the sequential system wont work tho...

seriously tho.. the best and most reliable and ultimately most fun way

Single turbo, and a Haltech e6x or E8...

beats hours of fustration trying to get it to start and run.. and hacking up a perfectly good chassis just to squeeze in the Twins which are woefully undersized anyway...

There you go,sounds like Ottoman recently did this particular conversion. Personally sound like a major PITA to me just to install a rotary. If it were me I'd sell the rotary engine,front clip etc etc. Pool all that together and go LS-1. Muuuuuuch easier can even get a painless harness if your electrically challenged. And when its done it will be a rocket! Also dont forget about the endless ECU programming available for stock GM ecu's. Id be willing to bet you could have a LS-1 in there and up and running faster,cheaper and much happier with the final product than if you installed the rotary. It just makes sense. A single turbo rebuild and rotary engine rebuild can be as much as a good used LS1. This is my opinion you go with whats right for you. Just look at all your options. If you can try and get a ride in any V8 powered RX-7 and I bet youll then be convinced!

Thanks.