With my 700R4 acting strange after my Transgo shiftkit install I have to look at buying a new trans

So I was wondering what is the max power (TQ,HP) each of the following could handle. As well as the cost.

1)Aftermarket 700 (probuilt)

2)Stock LT-1 T-56

3)Aftermarket T-56

4)aftermarket T-5

5)aftermarket Turbo 400

I am saving up to build a 350 or 400 as well so it needs to be able to handle a good amount of TQ. It will be a semi-daily driven car, not driven in snow or rain. I would use it for some drag purposes but for auto-X as well. I would prefer a manual, but it seems like a good manual would cost about twice the amount of an aftermarket auto.
All thoughts are welcome

Chris

 

i am brining this back from the dead cuz i thik it is a good question

 

i'd like to know too :-D

 

Wow its been a while since I have seen this thread. Anyways I ended up going with choice number 1.

Though I am still concidering going with #2 or 3

 

Well... my TH400 is good to at least 1,000 hp cause that was how much the car was putting out which this tranny came out of. Cost for my unit if you get it through Mike's Transmission is up to 3,850 bucks, got it a bit cheaper than that Then there's the good torque converter you gotta get... Mine's in the 800 dollar range. Really feels different than the cheapy 170 dollar TC that I was running. Totaly more transmission than I'll ever need but I was sick and tired of my other TH400 needing repair after repair.

 

add power till it pops and back it off a notch...


seriously though, ive seen T56s sit behind 470+ hp daily drivers that get abused all the time, and last thru several thousand miles and a couple clutches....

most street cars will never make enough power to break one.

 

I don't know much about automatics so I will cover the manual tranny's

The T-5 can handle only about 300 lb/ft before she starts jumping ship. Some guy have thrown more at it but they aren't as hooked to the road and get a lot of wheel spin. The day that they hook, BOOM, bye bye T-5. It doesn't like powershifting and can't take a lot of abuse.

A stock T-56 is rated to handle 450 ft/lbs stock but some guys have outrageous combos (LT1/LS1/Vipers/New Cobras) and they are still holding up. This tranny can take serious abuse and still run fine. As far as I know and read, an aftermarket T-56 can handle 500 ft/lbs, but like the stock T-56 I am sure this is an underrated number. T-56 is the way to go.

 

when they say 450 do they mean at the fly or wheels?

 

They mean at the input shaft or fly. But a lot of ls1 guys with heads and cam are putting over 420 to the wheels which is just a few more than 450 at the fly

 

most stock 700-r's will run well to 350.

a turbo 400 or 350 is better suited for someone who plans to race but for a street car that sees the occasional abuse a 700-r can hold a bit more.

if you were planning for over 500 i'd stick with the turbo autos or a good 6 speed. otherwise a well built 700 will work alright. make sure your rear is good as well. i know my stock one doesn't like alot of power.

 

when i am at the track i run what i have on the street meaning no slicks and my normal tires so i think the rear will be ok i hope

 

"most stock 700-r's will run well to 350."

Whats "well"?

my r4 has 78k on it, it works perfectly right now, my ONLY reason for thinking it will last a little is that it is an 87' r4, which was the year they beefed it up and made it better....my 350 thats going in next week is lurking around the 350HP area, im running the Comp cam XE268H cam, protopline vortecs and like 11:1 CR...so im hoping to get 400HP, but realistically looking at 350HP....im more worried about the torque.....my fear is that the first time i drag it's going to blow, that im going to stroll up to my local raceway, and on the first run it just bombs....

 

1500hp/2000ft-lbs monster trucks use TH400 trannies... I think they are pretty tough.

 

on a side note, my basicly stock L03 is starting to cook my 700R4....

good thing i found someone with manual swap stuff.....