TH400 power handling and RPM range - Hot Rod Forum : Hotrodders Bulletin Board -- Hot Rod Forum

Register FAQ Search Today's Posts Unanswered Posts Auto Escrow Insurance Auto Loans
Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> Transmission - Rearend
User Name
lost password?   |   register now

LinkBack Thread Tools
  #1 (permalink)  
Old 09-27-2003, 03:45 PM
Registered User
Join Date: Sep 2003
Posts: 2
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
TH400 power handling and RPM range

Hey guys -

I have a question for all you domestic guru's:

Right now I'm running a 6spd in my supra and it's just a ***** at the track -difficult to launch and tends to hurt parts on drag radials (like the rear i blew thur night) - should've never been on low profile drag radials...damn wheel hop.

The latest trend for drag supras is going with a custom TH400 setup - since no matter how much a toyota tranny is WILL fail eventually and can be costly to rebuild.

There are few shops in the USA building these kits and selling them for $4600 - $5500 (tranny, TC, drive shaft, adaptors, manual valve body, etc, etc...) - OUCH right?

I found a guy in Virginia who built a TH400 kit (tranny, 4k stall, driveshaft, adaptor..etc) for the Supra and is looking to trade for my 6spd / clutch -

My question: The tranny he has is a TCI tranny (reverse manual valve body) with PI 4000 stall with all adaptors to fit the Supra. Granted, I still need to find out exactly which TCI 400 tranny he has...even though he is going to fully freshen the trans.

But how is the power handling of the TCI 400 trans?
Will the tranny be able to handle 8000rpm shifts?

Car weighs ~3500lbs and makes 621rwhp @ 18psi and over 800rwhp @ 30psi - all thru the 6spd of course.

Another shop in Maryland (MSP Performance) has no issues with ATI tranny's and runs 8.30's on his drag Supra...but this is TCI, not ATI However, he thinks the TCI would be great....

You all are the experts...any tips would be great.

I've been doing "searches" for the past 2 days here and found alot of good base info, the tranny seems VERY solid and many folks put 500hp thru it - just thought I'd ask about a bit more power and RPM range - not to mention the sudden power deliver a big turbo delivers vs. the linear power deliver of a nice BBC.

I suppose, worse case: the Tranny fails after a number of passes and over the Winter I replace with something like: $1,000 for a new 1000hp handling TH400...not bad Maybe even less since I'd have a "donor" TH400?


Reply With Quote Quick reply to this message
Sponsored Links
  #2 (permalink)  
Old 09-27-2003, 08:42 PM
Deuce's Avatar
Registered User
Last wiki edit: Choosing a trailer
Last journal entry: Jan 13 2013
Last photo:
Join Date: Aug 2002
Location: Deuceland USA
Age: 69
Posts: 5,657
Wiki Edits: 6

Thanks: 0
Thanked 11 Times in 10 Posts

The Turbo 400 holds LS 6 454 450 horse engines easy. They make 500 - 525 stock. They were underated by GM. Rodders installed Open Chamber heads, bored them .030 or more and balanced everything and were at 600 to 650 HP pretty a heavy 70 Chevelle.

Then they started shooting NOS on them.......750 to 800 HP on the bottle

No problems.........

I say GO FOR IT ! !

Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 09-28-2003, 02:22 PM
Crosley's Avatar
Global Moderator
Last wiki edit: T-350 rebuild tech
Last journal entry: 1962 Morris Minor 1000
Last photo:
Join Date: Nov 2002
Location: ... USA
Posts: 9,278
Wiki Edits: 1659

Thanks: 963
Thanked 301 Times in 265 Posts

I've built T-400's for Federal Mogul blown alcohol funny cars.

The engine guys tell us 2200 - 2500 hp

This is a very serious T-400 with high amounts of special parts.

I had a 6-71 blown 468 bb chevy in a 69 Camaro in the 80's. On a Go-Power dyno the engine pegged the 1,000 hp needle.

The T-400 in the car held up well to my foot and 13 inch slicks.
Dont worry how old you are... it is the mileage on your body that adds up.
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 09-28-2003, 04:51 PM
Registered User
Join Date: Sep 2003
Posts: 2
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Deuce & Crosley -

Thanks for the info, basically I wanted to hear from some "real" world users and racers, the 400 swap is still pretty new in the Supra world, and the few shops making kits charge an arm and a leg.

They sound pretty solid even in stock form - especially if they can handle a large nitrous shot and still make it.

My real concern was it taking pass after pass with 800 more HP going thru it and snapping off 8000 rpms shift.

Crosley - you build a mean 400 tranny - Obviously, I'll never need anything quite as stoudt the tranny behind a blown alky car - but I would like the tranny to at least make it thru an entire season or more before needing a full freshening.

If that means buying / building more than I'd need - so be it. Being new to domestics - I'm not sure what you (crosley) or any of the local places would charge for an extreme rebuild...but looking at this: - 1000HP rated, for drag racing and the whole 9 yards is only $ in the Supra world - I image a build of an existing tranny would be even less?

Thanks again guys! -stay tuned
Reply With Quote Quick reply to this message

Recent Transmission - Rearend posts with photos

Quick Reply

Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last name), your email address and other required details in the form below.
User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:
Please select your insurance company (Optional)


Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

All times are GMT -6. The time now is 03:12 PM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright 1999 - 2012. All Rights Reserved.