what useage?
drag?
what power level?
the "super streeter" from p.a. is cheap, and pretty solid for a mild engine.
i used one of their "comp" c4's with a manual vb, and loved it. this was behind a 300rwhp or so 302, and then a well over 500rwhp combo, then back to a ~330 rwhp setup.....always changing. tranny never skipped a beat!
expect a GOOD converter to run an additional 500-600 for a c4, more for a nitrous, or purely race converter.