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My latest custom project- 4T80E swap in our 1997 Grand Prix UPDATE- Its on the road!

Trannyman95

Transmission Expert
I toyed with the idea for several years of doing this and have had a trans sitting here waiting to play with. The 4T65E has its limits and long known history of what breaks and needed improvements and several things we are still working on with them but limited time. I have always pushed something different just to say I did it :th_mischievious:.

I have well over 100 pictures of this swap currently and have posted a few of them up on our Facebook page. It is easier to plug them all into one spot and I don't have much time on the forums anymore, so love FB or hate it- it does help keep things easier and in one general spot to watch.

The fresh built turbo engine is bolted up to a 4T80E transmission and installed in the car. A few small details to iron out yet but most of the parts are sitting here ready to use, just lack of time to push hard on this project but should be finished up soon.

There were several obstacles to make this work! The engine had to move forward about an inch for the monstrous transmission to clear the back of the cradle. All new custom engine and transmission mounts were made for this to work. NO dogbone mounts will be used on this car so that opens up room on the top side. Moving the engine forward also buys room for turbo piping which is a plus! The factory front manifold was used more as a reference than anything else. There is only about a 1/4" of room between the manifold and the heat shield on the passenger side cooling fan, I am a big fan of thermal wraps on exhaust anyways and is much needed for this application. Custom manifolds/headers will eventually be built for this but probably not until spring time.

So is it worth all the work? Who knows, but there are so many benefits with this transmission in the strength department so the goal is to break it and see what and why. This transmission factory has a much stronger 30 spline input shaft, 7/16 pitch 1" chain with massive sprockets and support bearings, larger clutches end to end, good selection of gear ratios, and the best part is there are thousands of these in salvage yards cheap.
 

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Re: My latest custom project- 4T80E swap in our 1997 Grand Prix

I like it a lot....


By the way, the trans is running great. It's been two weeks and it feels good. Thanks.
 
Re: My latest custom project- 4T80E swap in our 1997 Grand Prix

****yeah dave

glad your tackling it and not me!

i get to enjoy shoving one into the 1st gen W subframe

i ****in despise bookface....are your pics viewable without an account?

btw...figured out the solution for the TCC/Armet 100 input shaft.

im shipping precision the converter and IS so they can cut the turbine hub for the Oring since that area is unstressed we'll get to keep the 1200hp rating of the IS and retain complete TCC functionality!

a solution always presents itself...

keep me updated bud

regards, James
 
Re: My latest custom project- 4T80E swap in our 1997 Grand Prix

Still debating this. Dave I may give you a call this week or next to talk to you about it.
 


Re: My latest custom project- 4T80E swap in our 1997 Grand Prix

What gear ratio is in this one your doing and please for the love of god post a million pictures on here and a how to write up!!!

This is a swap that's needed to be ironed out for a long time now!!!
 
Re: My latest custom project- 4T80E swap in our 1997 Grand Prix

i forgot to ask whether your using the 97-99 or 00+ 80e and with which year pcm? you gonna add a tcc exhaust hobbs/pressure switch or just tune out tcc function like we did on the Riv?

in my next iteration, i will be running a 2000 but with the 03+ IMS and harness swapped in to use with our 04+ rear harness. the front we will likely stick with the 97-99 80e for the 98-02pcm as im not sure i want use the 03 pcm/harness since the electrical work is pretty finalized up front.

a while back i came across the perfect combination of nc/NO solid state relays for iverting the one shift solenoid logic. god help me if you figured out how to fix that via the tech 2.... imma strangle yew.... ive actually been wanting to do some bench testing with changing the trans type in TINYtuner to see if the 80e is in there

ok im done lol have a good one dave
 
Re: My latest custom project- 4T80E swap in our 1997 Grand Prix

This transmission is from a 96 Aurora and has the 3.48 ratio. When I build a replacement it will get the 3.11 ratio.

James- the tune issues have been sorted out so that is not longer an obstacle :cool:. I will be using a 98 GP harness and pcm for this project. Trans type alone doesn't seem to get the whole job done so there will be a lot of toying with this but solenoid state is covered, and hey if I can get a 4L60E to work with an L67 file this will be a cake walk lol.
 


Re: My latest custom project- 4T80E swap in our 1997 Grand Prix

Please for the love of God do a write up when you have time.
kthanx
 
Re: My latest custom project- 4T80E swap in our 1997 Grand Prix

i'd like to see someone try and break it before i'd put too much faith in this swap as a solution to it all.
 
Re: My latest custom project- 4T80E swap in our 1997 Grand Prix

try to guess which diff/final drive planetary is the 80e


80e, GMR 1", OEM double, OEM 4t60 aka 7/8ths


look up the tow ratings of the caddy vs the W...quite a difference there...

the 80e is well worth the effort and offers several benifits over the 4t65
 


Re: My latest custom project- 4T80E swap in our 1997 Grand Prix

I knew there was a huge difference but this all makes the efforts of a built 4t65 pretty lame....... not to mention the money involved, even doing the conversion has to cost quite a bit less than a full tilt 4t65 build!
 
Re: My latest custom project- 4T80E swap in our 1997 Grand Prix

I agree with Jason though.

These can hold soooooo much more than a built 65 can..... And for a fraction of the cost.
 
Re: My latest custom project- 4T80E swap in our 1997 Grand Prix

There is hope

Questions

What axles did you use?
Where did you get those lime green wires? :D
 
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