Differences between 140hp and 160hp 3.1?

[Guest]

What did GM do to get 20hp from the 3.1?  I noticed the intake manifold is different, anything else?  Are they the same heads?

[z284pwr]

Umm, 2nd and 3rd Generation engines.  Lots of differences.  One is an LH0 2nd Generation 3.1, and the other is an L82 3rd Generation 3100

Heads are a lot different and flow better. Intake Manifolds have different runners and flow better.  Roller cam.  Better oiling.  More compression.  There are quite a bit of differences really.  Even though all the 3x00 hardware fits on the 2.8/3.1 block, so hybrid 3.x/3x00 engines are quite common and can be done up to make some pretty good power.  Colin over at 60*V6 has a Sunbird with a pretty built up hybrid and is one of the only, if not the only N/A Hybrid in the 13s.  Not bad for a little V6