TH-400 in 86 Vette
Safety Car
Joined: Apr 2004
Posts: 4,532
Likes: 7
From: Lahaina Hi
I would stick with the 700 r4 the 400 turbo is not any stronger than the 700r4 if built right.
http://www.transmissionhead.com/
http://www.700r4l60e.com/
http://www.transmissionhead.com/
http://www.700r4l60e.com/
Last edited by REDC4CORVETTE; Mar 2, 2005 at 03:31 AM.
Le Mans Master
Joined: Feb 2000
Posts: 9,715
Likes: 27
From: Kempner Texas
Originally Posted by kenv
why?----- I`ve got a th400 in my C-3, if I take that car to work, (40 miles each way) I use a full tank of gas by the time I get back home. With the overdrive in my `87, I can go most of the week, without gassing up. 
If that's the case, there's something else going on besides just the loss of over-drive.
Jake
Team Owner
Joined: Sep 2001
Posts: 62,161
Likes: 1,733
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
Originally Posted by drjimmy
Has anybody converted their 700R4 to a TH400? Just wondering what I can expect if I go this route.
Drifting
Joined: Nov 2002
Posts: 1,905
Likes: 1
From: 2003 Points Champ Great Lakes Corvette Challenge; 2006/2007 Winner MSD True Street
Originally Posted by REDC4CORVETTE
I would stick with the 700 r4 the 400 turbo is not any stronger than the 700r4 if built right.
http://www.transmissionhead.com/
http://www.700r4l60e.com/
http://www.transmissionhead.com/
http://www.700r4l60e.com/
One link said the 700r4 will handle 550-575 hp or 625-650 hp for the strip 700r4. The other link said it's 700r4 will handle "up to" 600 hp and 450lb of torque.
Well my friend, I exceed all those numbers and have blown 7 (seven) 700r4 rebuilds. My T-400 will hold "up to" 1200 HP and Lord knows how much torque.
A T-400 can be built to exceed ANY 700r4. There are just too many weak links in the 700.
My two cents.
Matt383
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
Originally Posted by drjimmy
I'm running ~400 hp at the motor plus 100hp nos.
A 700R4 CANNOT be beefed to be as strong as a TH400 can be beefed to be.
RACE ON!!!
Racer
Joined: Feb 2005
Posts: 387
Likes: 1
Here's the url for best 700r4 builders in the country.
http://www.transmissioncenter.net/highperflist.htm
Buy the MegaRaptor, Level 4.
http://www.transmissioncenter.net/highperflist.htm
Buy the MegaRaptor, Level 4.
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Verdad Gallardo
Le Mans Master
Joined: Mar 2001
Posts: 9,464
Likes: 1
From: Modesto CA
TH400's are stronger than 700R4's PERIOD.
Now, I've heard of a place that can build a 700R4 to live behind a 750bhp engine. Even seen it with my own eyes. There's only ONE of them, and it's in an 91 ZR1...which was converter over to the 700R4 with an 8" 5000 stall converter. The engine is an LPE 385 LT5, with a 250hp Direct Port Nitrous Injection. They even put in a B&M Hammer Shifter and made it look STOCK!
BTW: The car runs bottom 10's, I think ON THE MOTOR.
Now, I've heard of a place that can build a 700R4 to live behind a 750bhp engine. Even seen it with my own eyes. There's only ONE of them, and it's in an 91 ZR1...which was converter over to the 700R4 with an 8" 5000 stall converter. The engine is an LPE 385 LT5, with a 250hp Direct Port Nitrous Injection. They even put in a B&M Hammer Shifter and made it look STOCK!
BTW: The car runs bottom 10's, I think ON THE MOTOR.
Former Vendor
Joined: Jun 2001
Posts: 7,204
Likes: 6
From: St Marys PA
I see this poist was resurrected from the past. Above I said I was going to try dads T350. Well I went one step further recently and installed one of my own from Rossler.
Used the adapter piece and it went in like a dream. The case is MUCH smaller on these T350 than the 700r4s and made installation of the tranny itself and the C beam much easier. Went with an 8" converter ~5000 stall.
A 700r4 can take some serious abuse if built right and taken care of. Heat is the killer. A simple trans cooler for 40 dollars can make one live in the worse of power conditions. Mine lasted a brutal 3 years with hundreds of runs and still performed like new when sold to NitrousSam. I am sure he will enjoy many more runs with it behind is 406.
T350 are pretty tough, upto about 800hp according to Rossler. Then the 400s take over - followed by the glides that take a zillion HPs.
With each of the trannies the more they support HP wise, the less they have internally to funtion properly. Sorta along of the lines of the KISS principle.
Used the adapter piece and it went in like a dream. The case is MUCH smaller on these T350 than the 700r4s and made installation of the tranny itself and the C beam much easier. Went with an 8" converter ~5000 stall.
A 700r4 can take some serious abuse if built right and taken care of. Heat is the killer. A simple trans cooler for 40 dollars can make one live in the worse of power conditions. Mine lasted a brutal 3 years with hundreds of runs and still performed like new when sold to NitrousSam. I am sure he will enjoy many more runs with it behind is 406.
T350 are pretty tough, upto about 800hp according to Rossler. Then the 400s take over - followed by the glides that take a zillion HPs.
With each of the trannies the more they support HP wise, the less they have internally to funtion properly. Sorta along of the lines of the KISS principle.
Racer
Joined: Feb 2005
Posts: 387
Likes: 1
it REALLY depends on the weight of the vehicle. My friend had a 3/4 ton chevy truck with a 383 that would eat up a th400 in about a month of hard use. too heavy. The ultimate would either be an Allison, or a 4L80E (built)
Drifting
Joined: Nov 2002
Posts: 1,905
Likes: 1
From: 2003 Points Champ Great Lakes Corvette Challenge; 2006/2007 Winner MSD True Street
Originally Posted by CFI-EFI
A 4L80E is an electronic overdrive transmission, based on the TH400.
RACE ON!!!
RACE ON!!!
I was going to say the same thing.
I've got the 4l80E in my GMC.
Tows 9,000 lbs!!
Matt383
Racer
Joined: Feb 2005
Posts: 387
Likes: 1
Drifting
Joined: Nov 2002
Posts: 1,905
Likes: 1
From: 2003 Points Champ Great Lakes Corvette Challenge; 2006/2007 Winner MSD True Street
Originally Posted by 4bblC4
true, but the 4L80E can handle more power than the th400.
Ok. From what I've learned, the 4l80E IS at T400 with overdrive and an electronic shift (hence the "E")
With that being said the 4L80E may actually be WEAKER because of the over drive. (More parts, shifts, bands, etc.)
My two cents.
Matt383