700r4 Trans with an LQ4

[gunrunner95]

Okay so I have an 89 Silverado with a stock 350 and a 700r4. I'm waiting to do the popular LQ4 swap this summer perhaps so I'm doing research on it. My transmission was rebuilt back in November and has less than 1000miles on it so I'm hoping to use it, I know its possible to the old style of transmissions but I'm not clear what all is necessary/what kinds of issues may arise.
Any help is greatly appreciated Thank you.

[rickpilgrim]

LS motors have a longer crank on the flywheel end so that needs to be addressed with a bell housing spacer. Also, your LS has a different torque curve so use a mild stall speed lockup converter like GM does to get it in its power curve sooner. You may want to alter the shift points in the 700R4 also. Set your TV cable on the tight side and you should be good to go.

[gunrunner95]

Thank you Rick I appreciate it.

[Tom]

Originally Posted by rickpilgrim

Also, your LS has a different torque curve so use a mild stall speed lockup converter like GM does to get it in its power curve sooner.

I'm a little confused, a mild convertor would be like the 350 uses, not high stall speed. LS's don't make torque until they rev, so they need a looser convertor to stall at a higher speed. To get any more mild then what a stock 5.7L uses you have to get a diesel convertor.

[rickpilgrim]

Originally Posted by Tom

I'm a little confused, a mild convertor would be like the 350 uses, not high stall speed. LS's don't make torque until they rev, so they need a looser convertor to stall at a higher speed. To get any more mild then what a stock 5.7L uses you have to get a diesel convertor.

What I mean by a mild stall converter is one with about 2200-2400rpm stall vs the 5.7's 1800-2000rpm stall. In laymans terms mild stall would equal looser.
A diesel converter is a 1000-1400 which would make milage improvement on a 5.7 but really act like a 4 cyl takeoff on an LS motor.
Hope that clears it up