Heads and cam will work to just over 300hp RW with a stick. Auto should be mid 250's. 3.50 rear gear with a C4. 2750 rpm with a 25-26" rear tire @65mph. Leave the stall. Its not that it cant use less, but it will turn into a bigger dog if you tighten up the converter.
Headers, Headers. Try and find 2.5" collecters, 3.0" works ok . May even consider 2.5" muffler and tail pipes.
Make sure you don't have the junker HiPo chrome air cleaner with 2" element and drop down base. A 1/2 in rise base plate with 2-1/2" -3" element will fit( depending on manifold & spacer). If your not just starting to scratch the paint on the underside of the hood your air filter is too short.
Your combo doesnt sound horrible, but if you bolt a bunch of stock pieces to it, you can't expect much more 1/2 way between stock and where it should be.
Mismatched 289 combo
Moderator: Team
Re: Mismatched 289 combo
You got handed the worst combo of little motor, no compression, no converter, no gear. Leave it alone. Spray it with a cheap 150hp plate kit. Dollar per ET it will be the best $ spent by far
Re: Mismatched 289 combo
A 150hp plate for 500ish lets him keep the tall gears, exhaust manifolds, pooch converter, and all. As a plus, tje low cr 289 may not even need the timing reatarded on a 150.