How much can a 700r4 be built to withstand?
Logically the answer is anything depending on the size of your pockets. Lets say im on a SORT of budget, i want the tranny to be able to handle 800 ft/lbs, but i dont want to use up my life savings.

Are there any Overdrive alternatives? I still need to drive this vehichle on the highway....

I dont feel that 800 ft/lbs is a very demanding number... I mean if i build a simple nitrous motor it will EASILY be beyond 800 ft /bs with todays technology

 

Im not sure how much this kit can take, but everything is heavy duty and this runs I think under $550. Im not sure if you can rebuild the tranny your self, but here is the link for the kit
http://www.pro-built.net/index.cfm?f...ct&productid=5

Also very good kit everything is there you need I believe.

 

Even a built 700r4 wont take 800 ft lbs. of torque for very long. Try a built TH400. If you want OD, Gear Vendors makes a TH400 with an OD unit, it's supposed to take 1200 hp.

 

They say that the stock drivetrain on a thirdgen can handle 450lbs of torque.

 

What exactly does gear vendors offer? A NEW TRANNY ? Or a unit that you attach to your tranny?>

 

Gear Vendors bolts onto the tailshaft of the transmission.

it has a 20% OD ratio.

besides just bieng an OD unit, it will turn a 3speed tranny into a 6 speed, and a 4speed into an 8 speed.

IT does this becuz it can engage the overdrive in any gear at any RPM that you choose.
This allows for increasd ET, cuz it keeps the engine in its RPM range for longer.

 

so when they say they're selling a 700R4 it's not the 700r4 and the unit it's just the unit?

 

True.


BTW my 700 is said to handle around 600 horses with decent reliability. I got it built as much as possible with off the shelf parts. Cost about $1300 out the door w/ converter.

If anyone knows anything about this please reply. I was under the impression that the 4L60E and 4L80E were electronic versions of the 700 and that the 80 was just a heavy duty 700. Is this true, or are they completely different animals? If so the 4L80E is the weapon of choice for TT SBC engine builders.

 

If you were sure that you would need to have a tranny to hold 800 ft/lbs and you still wanted over drive the easiest (maybe not cheapest) way would be to put a 4l80-e behind the engine because it is very close to a th400 with an overdrive. the internals are beefy compared to a th700r4. they used these trannys behind the newer chevys in the 2500 and 3500 trucks with the gas engines i think. i am pretty sure that they use it behind the new vortec 8100 as well and that is a pretty stout engine.

 

The 4L60E is only rated to 370 ft/lbs by GM

4L60E @ GM Performance