The 4t80 shoehorn

[Prospeeder]

Guy on a-body.net put in a 4T80 behind his 400 horse Turbo 3.8 in his 84 Buick Century, had to modify it alittle, but he had a big thread about it over there if you looked around, he might have a few tips on it

[TurboGTU]

First disassemble the caddy axles. Take the shaft to your machinist buddy and have him move the snap ring grooves as close to the center as the splines will allow. About 3/8 inch. Do this to both ends, all four snap ring grooves. Then cut off that much from the ends. This shortens the axles 3/4 inch. Next disassemble the outer joints, removing the balls and cage, save the center portion the part that fits the axle. Next disassemble Fiero manual transmission axle outer joints. Auto axles will not work, they are too small. Save the outer part with the axle stub that goes through the bearings and drives the wheels. Now put the part you saved from the Deville outer in the Fiero outer, using the balls and cage from the Fiero outer. Now you have an outer joint that fits your Fiero and fits on the Deville shaft. Now reassemble complete shaft. You should end up with a shaft that is 3/4 inch shorter with caddy tripod on inside and fiero c/v on the outside.

Think i might try this...maybe I missed something using the tgp outer joints.


Prospeeder is that pontiacjeff?

[TurboGTU]

Nope didn't miss something. Took them both apart and the Aurora outer cv guts are smaller than the TGP outer guts. Tried using the Aurora part that has the lock on it into the sphere and balls and outer shaft from the TGP, didn't work. Going to look at Caddilac outer cvs and look at other cars CVs to see which works on the tgp outer.

[Prospeeder]

ahh you know what, sorry but i looked back, he used a 4T65E

[TurboGTU]

Intake arrived yesterday.  :icon_mrgreen: Just what I needed. Uses a larger throttle body much like the 3500. Its a drive by wire setup, but I will be using a ford TB or fab up the Ls1 throttle to work.

Before......



After........

[TGed]

Why is that manifold reversed?

[TurboGTU]

On the Equinox its intake is on the passenger side. So it had to clear where the PS pump would be. Of course  I didn't see a PS pump on Equinoxs I've seen. And my setup will need to face the intake the same way.

I went to the junk yard agan and messed with some Caddy axles. No dice. Next step is to use 97+ Grand prix strut and knuckle assymbly.

[TurboGTU]

Trying to put this in the front burner, It's been sitting to dam long. Only things holding back the swap is the CV axles. Other then that time and a cent or two. Going to talk to a CV axle shop about frankengoating these. Pulling the LG5 out of the Beretta and working on some head work. Going to the local yard to see if a PMIII is still there(some ass munch removed the lid let rain in) and remove some parts from it. 

[Shifter23]

Keep us posted!

[TurboGTU]

1990 Seville cv axle outer looks like it might work. The axles I was looking at the J-yard were of the N*/4t80e variety. Never though of these. Will looking into thise.

[TurboGTU]

As much as I like to finish this project, life happens. I've been the only tech at the truck shop. Moneys good but haven't had time to really work on the tgp. Custom work cost money.

Anyway, Found this site rockfordcv.com it gives the brake down of part numbers for our cv axles cage, ball bearings and outboard inner race. But the most important part for me is the ball bearing and cage numbers. I'll measure the distance between the outboard inner race from the aurora axle (star thing that rides on the shaft) and the outboard joint from the TGP (part that goes into the wheel hub) to come up with a ball bearing size required and that size will give me the cage required and off to tear some other cv axles for their balls and cage at the J-yard.

Another thing I found out is that the Torque converter I got from the Aurora is a Non-viscous. 441 sticker on converter. The other fail prone viscous are the 440 labeled ones. That's something less to worry about.

[TurboGTU]

Think I just hit jackpot. I will replace the inner race from the outbard. THe race from the TGP has 32 spine hole. The olds 4t80 shaft has 34 spines.  Looking at 79-84 toronado, riviera, eldorado seville, 90-99 lumina, 90-99 apv lunmina, 82-96 chevy truck, 91-98 Dakota saginaw desighn, 82-96 s10/ blazer and GMC sonoma, bravada, Jimmy.   This will retain the TGP outboard joint , cage and balls.

My thought of getting bigger cage and balls won't work since the race and joint have to have the groves for those balls and cage has to fight tight in the joint.

Well I'll see if I can get some time during lunch and do a quick look see.

I'm guessing on the luminas it's the 3800 variety. SO maybe 98-99.

Edit due to having wrong cars. These are right.

[TurboGTU]

Got the cage, balls , race from a 96 4x4 s10 blazer.  They fit perfect in the TGP joint and 4t80 shaft.  The TGP and s10 both have .750 diameter balls. Other w-cars I saw had smaller size but were the 3.1, 3100 type. Now on with the build.

[Shifter23]

Any progress on the build?

[TurboGTU]

I've been away from the TGP for months. So much so that the garage sprung a leak and ruined my 4t80 the non-viscous converter is safe though. The original tgp engine that I loaned to the Beretta is all rusted too. Had pulled the heads and walked away for over a year. Needless to say, I'm shopping for another 4t80, I'm also planning a 3900 with LS1 forged pistons and 6in rods using either the TGP crank and have it Cryo-treated or use the 3900 crank and have that cryod but use an external trigger. I have two VGT turbos ready for a twin setup that flow enough for my goals. They each powered a 2007+ 5.2l isuzu NPR.
I'm planning this out as my new daily grind vehicle as the grand am I'm driving is neering 230K miles on the original drivetrain minus heads. I know it will still kick up to or past 300K miles but give me an excuse to spend my money on the TGP rather than a new/used boring car.