Automatic Turbo 2 Swap
 

Let me start by saying I have a 87 GXL with an auto transmission. The car has 89k original miles and the transmission runs flawlessly. Now the engine on the other hand is on it's way out.

I have recently come across an s4 T2 swap that I plan to drop into the car and use the existing auto trans.

I just had a couple questions:

Are the US NA auto transmissions the same as the Japanese auto transmissions? I was also wondering if the transmission will shift properly using the S4 T2 Ecu that came with the swap?

For the flamers, the car is for my mother's commute. It will be boost with no mods other than a wide band. :icon_tup:

The NA auto transmission, to my knowledge, is in no way whatsoever strong enough to put up with a turbo engine..

As far as shifting, it should work fine AFAIK..

I am trying to remember from WAY BACK...


I "think" this transmission is the same one used in the Pantera supercar. I think it should hold up to the turbo just fine.

That being said, i am not sure if it is compatable. (balancing of the engine, etc.)

Rob R.

I searched the topic before I posted, and I think I saw a post where someone said they had an automatic t2 swap with a little over 250whp and the transmission was fine but the shift patterns were kinda eratic.

I'm sure on stock boost without daily power braking the transmission will hold up fine.

Thanks for the input guys any experience or advise is welcomed :)

not sure, and it should, but you will have to make sure you hook up the AT computer like it should be.

I haven't even looked, but if there is an AT ecu separately then it probably won't be disturbed. I'm just going to swap the main engine ecu with the turbo one.

theres no AT ecu... its all a bunch of relays in the front of the car and nothing more...these transmissions are more mechanical than electrical

and the engine is seperate from the trans.... as long as you have the flexplate and counterwieght that the flex plate goes on your good...

you're going to be pretty much in uncharted territory. the auto will work but it sure isn't ideal for turbo cars. the FDs were slugs also with the optional auto trannies even though they held the power if everything wasn't perfect the shifting would be erratic.

i try my best to talk people into manual swaps, because the 7's auto tranny is the ONLY thing i do not care to learn(about 1 in 100 rotaries ever were bought with an auto).

almost be better to adapt a Turbo 350 or powerglide to the engine, then the sky is the limit for mods and power handling upgrades.

I'm really excited to see how it performs.

It's okay if it's a slug the car only has 89k original miles and I bought it off the original owner with well documented maintenance. I bought the car for my mom to commute in, but as the oil control rings went out and I came across a turbo 2 swap for a price that I couldn't afford not to buy I decided it was time to take that step into the unknown.

I'm also going to start a build thread with details!

The Japanese autos were turbos so who knows if they are the same transmissions found in the USDM cars. And the S4 did not have an auto transmission computer like the S5's.

i'd prefer to have the basic auto versus the later model computer feedback type. although i'm sure the series 5/6 autos were built with better parts to handle the additional power. differences between the series 5 and 6 were probably negligible or none at all. series 4 were probably carbon copies of the early autos that were used since the 70's, which likely includes the JDM series 4 turbo auto trannies. but less interaction with a computer to control it means less problematic, especially since the FCs almost never run as they did when new and would probably result in stalling issues and other erratic issues with early or late shifts, but that all can be remedied by a competent auto transmission tech.

it's been at least 15 years since i have had any auto transmission apart on a bench so...

I'm an ASE master tech myself, however l don't have any interest in overhauling the trans haha

I remember Rob of Pineapple Racing once telling me that the early autos [FB and earlier] were very durable, but that the FC ones were comparatively awful..

I actually thought of going this route awhile back and almost did.
But My health got better,and I can now walk around,so I can manage a manual.I like my 5 speed anyways.
I am going to watch this build for sure!

I know people have done it, but there nothing in depth shows up when I search it. I stock s4 T2 swap on a used engine shouldn't really put out much more than its NA counter part. My mom drives like an old lady so I don't think it will effect the durability of the transmission much.