Sorry, the 50# was a brain fart.I just put a set of 50# in a '96 LQ1 (3400 DOHC) turbo project... I plan to use a 65# in the Bonne.

More pics comparing the -80 and the -65. Forget billet input shafts and hardened output shafts... who needs them when these parts are bigger, stronger, and stock!

Look at the ouput shaft!





and the input shaft!



more pics of the differential. I just finished building a limited slip for a customers 4T80. I plan one for this, too.







While I am machining gears tomorrow, I'll be fabricating a bracket/brace for the tailshaft housing. Also, the flywheel needs 4 holes instead of 3. And the gear selector lever needs to be relocated to clear the crossover pipe.

More pics as the work progresses.

How much more horse power does it take to turn the -80 as opposed to the -65? That'* what I'm wondering. :?

That would be my first question as well. Drivetrain loss may be more.

I forgot...

The -65 weighs 195# with converter, the -80 weighs 245# with converter.

As for drive losses, I'm sure thee will be some... but the 3.71FDR will more than make up for any torque losses vs. the 2.97FDR of the -65. The forst thing I'll do is dyno it to see the difference. I have a good baseline to compare it to.

Sorry the project stalled (no pun intended!). I need to get the car running again before Oct. 1 as my current driver (the "race car") is going down for a beefier clutch and transmission mods. I will likely have some more info the week of 9-25. The trans is mounted to the engine, flywheel drilled for the Caddy converter. The hard part is going to be mocking it up. I have ot have it in the car due to the front engine mount in the Bonne. It will be the only locating mount I have to work with (unless I decide to go W-body mounts and fab-up a front engine mount pad and rear trans pad, then I can use all GM mounts. I will have to build a tubular rad support so I can run upper dog bones... still mulling that over).

Very interesting project, I'm looking forward to seeing how this all works out. Thanks for posting the details here, cool of you to share your project

Just wanted to point out a detail on the above. The Final Drive Ratio inherant in the 65 is 3.29, it'* the chain and gearset combination that determines the actual FDR. 3 sets are currently used offering 2.92, 3.29 and 3.69 ratios.

Cheers,

Since you brought it up, there are 9 possible FDRs for the -65E based on 3 differential planetary gear sets and 3 chain drive sets. The most common used FDRs are 2.86 (3400 N- and W-), 3.05 (3800 W-, H-, C-, and E-) and 3.29 (3400 U-vans and Grand Am GT), all of which use the 35/35 chain gear set. The 2.93 is only used in the -HD behind the 3800 */C and is derived from using a 3.29. A 3.42 was used in the '97 Z-34 (3400DOHC) Monte Carlo. The only GM factory use of the 3.69 is in Buicks destined for China with the 2.5L 60deg V-6.

Good info, I wasn't aware of the others besides W and H bodies

Cheers,

thanks for the update Jeff, i will be staying tuned for the next installment. I cant wait to see how it turrns out....

thank heaven this 98 riv has such a large engine compartment, lol
that and the massive rear compartment of the 442...(the rear turbocharged 3800 would be the only one we'd use the 80e with, the front doesnt need it, but some hard launching with a fat *** 442 would def require the extra girth of the 80e!)

i wanted to ask you this (sorry i didnt include it in the email) what if any problems have you come acrost regarding the rear manifold and/or downpipe clearance with the larger planetary section of the 80e?
i'm asking since eric wants to get the pacesetter headers, and i'm curious as to whether i may need to fire up my torch, when the 65hd goes and we drop the 80e in...

also which converter are you using? the 4.0l aurora or 4.6 N*? is it a kevlar or carbon fiber TCC material unit?
i'm thinking an 01 or newer 80e with the carbon TCC would be best for the riv since eric doesnt mind the tcc lockup and we really have no desire to PWM it like they are supposed to vs the older kevlar clutch material. I have heard that you can install the carbon TCC converter in a kevlar vehicle but not the other way around due to the difference in the PWM of the TCC solenoid.

your thoughts?

Regards, James