: Performance transmission



eldorado1
10-28-04, 02:56 PM
I am pulling the cradle out to install the exhaust crossover (yep. you win Bbob! :worship: ) And while it was out, I thought I'd get some opinions...

First off, I have a 300HP engine, and a vin Y/275HP tranny and torque converter. Now, how much of a difference would switching the TC to a VIN9 do? I think their stall is a couple hundred rpm higher? Is it going to make any difference at all? 0-60 times? Or just "it feels a little quicker", but no measureable difference... Also, I was thinking about switching to the 3.71/3.73 gears (not sure which it was). This probably will make a difference in the 0-60 time. How much so?

btw - are there any stock converters that are swappable for a higher stall? 2500 would be great...... I bet I could peel the tires then! :D

also, don't argue with me about traction control this or ECM that... Everything is aftermarket/100% controllable by me on this beast.

BeelzeBob
10-28-04, 03:35 PM
See all the other posts about higher stall torque converters....they are definitely the way to go and probably the biggest bang for the buck in terms of performance.

The 3.71 final drive is definitely a plus, also. You can't beat low gears and high stall torque converters for off the line performance.......

eldorado1
10-28-04, 06:20 PM
Well, assuming a 298mm TC (which I am not sure is correct for the 4t80e), the approximate stall speeds are 1800 and 2300rpm. Is there going to be *any* measureable difference with just 500rpm higher? Same question for the 3.71 gears... I guess I'm looking for numbers - anybody have any clue? Dennis? How's your 3k stall TC doing? :drinker

dkozloski
10-28-04, 06:41 PM
Low gears in a daily driver are not a good thing. I have been there and done that. I always wound up in the middle of a trip wishing that it was back like it was. Besides Stroker McGurk says that you can't feel less than 10% in the seat of your pants. Loosening up the TC is a good thing. The only downside there is that in daily driving it feels like peanut butter drive with an old two-speed PowerGlide.

danbuc
10-28-04, 11:38 PM
bbobynski, do you happen to know which past threads mentioned the torque converters? I was just wondering who had the best prices and the best products. I also wanted to know if the 4T80E transmission uses a specific torque converter just for itself or does it share a common design with other transmissions. If it did, it would be much easier to find the right one. Thanks in advance
:)

foo
10-30-04, 04:29 PM
How much power can the 4t80e take? If i rebuild my engine and run it up to 500HP or thereabouts will it blow up the tranny? I assume it will but I have to ask anyway :)

eldorado1
10-30-04, 04:43 PM
How much power can the 4t80e take? If i rebuild my engine and run it up to 500HP or thereabouts will it blow up the tranny? I assume it will but I have to ask anyway :)

Transmissions are built with a fair safety margin. Take the fiero and the getrag/isuzu 5 speeds. Both were originally behind 4 or 6 cylinders, 140hp max. There are a lot of them running 300+hp v8's now. If you want to go to 500hp, I would highly recommend getting bigger/better/more clutchpacks, limited slip, possibly a upgraded converter. Everything else "should be" fine. Domestic performance sells a "bulletproof" 4t80e as well, might want to check that out. I think it was around $3k though :eek:

eldorado1
10-30-04, 04:46 PM
bbobynski, do you happen to know which past threads mentioned the torque converters? I was just wondering who had the best prices and the best products. I also wanted to know if the 4T80E transmission uses a specific torque converter just for itself or does it share a common design with other transmissions. If it did, it would be much easier to find the right one. Thanks in advance
:)

Do a search for "torque converter". There's a good 4 or so threads about it. Yank and SAE (I think that's right) were the companies listed. I too am curious if the 4t80e shares any converters in common with any other transmissions. If I can find a looser converter in a 4L80 or something....... Aww the heck with it, I'm putting the engine back in today anyways. Guess that'll wait until a spring project or something.

speedyguy
06-08-05, 11:38 PM
Good news is the trans will take quite a bit of hp especially from the Northstar. You could probably get away with 400hp. after that and you will want to look into performance parts.

There is even more good news. Most cores from old Cadillacís are not that bad when it comes to breakage or major repair issues. The 4t80-e tends to be a good core.

The bad news is the 4t80-e is not an easy rebuild. There are not many who can actually do a good quality job.

Ty

danbuc
06-09-05, 02:05 AM
http://protechtransmissions.com/about.html
This is the place to go if your looking for a high-performance rebuild for a 4T80E. When I spoke to them, they said that they would sell individual parts for various other transmissions, but the 4T80E would have to be rebuilt in-house, due to it's complexity. Their rebuild, a nice yank converter, and a good LSD would make for one hell of a tranny. They are in Harriman, NY though so you would have to ship them the tranny, or drive the car there and leave it with them. They have some nice stuff though.

davesdeville
06-09-05, 03:47 AM
Wow this is an old thread. My 2 cents is try to find a Getrag 284 5 speed manual to swap in if anyone wants a fun project that they can take pics of and write up a how-to for me :D