stock lsj exhaust manifold vs. gmpp extruded/honed manifold...

how much of a difference are we talking?

 

IMO not enough for the cost. Go with a real header.

 

well i have a 2.2 so both would be an upgrade.. just wondering how much of a difference in performance it would be..

 

All by itself, not really a noticeable gain. It's like getting a downpipe with a stock manifold and stock cat-back...you kind of need all three to see the full gains.

And for the money of the GM manifold, you'd be way way better off getting a real header, as noted above.