Extreme Street no more!
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From: Spokane, Wa
Extreme Street no more! Selling my T56 and my nitrous stuff for a TH400 and hefty solid roller to complement my new DFI kit. Decided it'd be best to sell my T56 before I start racing the car. I'd rather upgrade to a TH400 for a few hundred now, than be stuck with a 1900 dollar viper rebuild later. I plan on keeping the 4.71 gears, and winding this motor up into 7800 range. Stall in the 4000-4500 range... should make for stellar gas mileage on E85 
Time to start trailer shopping as well...
Time to start trailer shopping as well... Trending Topics
400 is tuffer, and if your going to make the converson to drag only, why do a th350. They are cheaper but if just want to show up and run pass after pass with not having to worry, th400 is the way to go along with a 9inch.
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10 Second Club
iTrader: (26)
Joined: Jul 2005
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From: Spokane, Wa
Buddy of mine has run a TH400 for years here at the 800+ hp level in a heavy *** car. If the cost is the same, and the TH400 holds up better with the t-brake, that's where i want my money spent. I understand the power loss and such, and I'm not making a ridiculous amount of power, and my car isn't heavy either. Once I pay for all of this upgrading, a single plane and 300 shot is probably a year or so down the road. I have the shortblock for it, might as well use it 
...I understand the power loss and such, and I'm not making a ridiculous amount of power, and my car isn't heavy either. Once I pay for all of this upgrading, a single plane and 300 shot is probably a year or so down the road. I have the shortblock for it, might as well use it
They are cheaper
but if just want to show up and run pass after pass with not having to worry, th400 is the way to go along with a 9inch.
T350 trannys take less power to turn and weigh less than a 400, i like the 400 dont get me wrong.....
12 bolt will do just fine, it also weighs less and is more efficient!
If it is a race car i would not do either tranny get the weight down and put a glide in there! why a glide? Glides lauch less violent than either of the TH designs....
Last edited by 96lt1m6; Apr 4, 2010 at 03:56 PM.
The LT4 that we are building for the Shootout this year will be backed by a TH-350. First gear choice is a big issue, because we are not allowed a wheelie bar. I have one with a 2.75 and another with a 2.52, but there is a good chance that we will have to spend a few bucks to get to around 2.10. Of course whatever we bring will have aluminum drums, etc.
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From: Spokane, Wa
Transmission choice depends a lot on what the final application and class rules. A glide is cool, but in a heavy, low HP car a three speed is often faster. We run a TH-200 in my Stocker, because it is faster than a TH350.
The LT4 that we are building for the Shootout this year will be backed by a TH-350. First gear choice is a big issue, because we are not allowed a wheelie bar. I have one with a 2.75 and another with a 2.52, but there is a good chance that we will have to spend a few bucks to get to around 2.10. Of course whatever we bring will have aluminum drums, etc.
The LT4 that we are building for the Shootout this year will be backed by a TH-350. First gear choice is a big issue, because we are not allowed a wheelie bar. I have one with a 2.75 and another with a 2.52, but there is a good chance that we will have to spend a few bucks to get to around 2.10. Of course whatever we bring will have aluminum drums, etc.
Looks like I'm getting a coan TH400 with a brake, and a protorque 4000 stall converter. I think dollarwise this will be one of best investments in my car's performance and reliability, this swap will only be a few hundred dollars. Don't get me wrong I can't wait to get my hands on that DFI software, I'm done tuning this clunky stock PCM 
FWIW I always assumed I'd have a stick in this car, and that's the main reason I went with a 9" in the first place, reason 2 being I got a great deal on it. Wish i had the cash for star flanged and gun drilled axles, but then again I'm on a budget so it has s/t axles and a steel spool. Guess I'll just get serious with the weight reduction, and try to get down to a 3000 pound raceweight. Don't get me wrong. We all build according to our own plan. When you are done you should have a rock solid drivetrain. There are tons of future upgrades that you can do if you start chasing those tenths. As this is a discussion forum, I just wanted to throw out some other ideas. It's your project, have fun with it!
I agree that it is a bit overkill for what you have now, but who knows what you will think up in the future so I guess its a forward thinking decision. You'll be faster then the t56 for sure!!
Welcome to the stalled auto club, say hello to nasty 60's.
Welcome to the stalled auto club, say hello to nasty 60's
. 
You wont go wrong with ProTorque, that was my first converter back in the day and Joe Rivera was very helpful and customer service was excellent, In fact I have not had better customer service from ANYONE else....