I was wondering why the LT1 in the Corvette has like 320hp where in the F-Body it only has 275. what parts in the engine are diffrenent?

 

f body has 275-285hp, vette has 300hp in LT1 form... no real differences in the motors (vette has a 4 bolt block, but that does not affect power output). Power differences come from the better exhaust setup in the vette, which is a dual setup, unlike the y-pipe setup in the f bodies... the different intake setup (airbox I mean, not intake manifold) on the vette may also contribute some to power differences.

 

GM has also been known to underrate the f-body just so as to not tick off Vette buyers.

 

GM did not underrate the LT1 f-bodies, the Vettes actually do have more HP. The difference though, comes from the air intake and exhaust rather than the engine. The only difference engine wise is that the Vette LT1s are 4 bolt, while the f-body LT1s are 2 bolt. There may also be a slight difference in the cams from year to year or model to model, but it's not enough to make more than a 1 or 2 HP difference power wise. The power difference is from:
1) air intake. The Vettes have an intake that is basically the same as a Firehawk/WS6 ram air (just without the functional ram air hood). This intake if you aren't familiar with it is a huge filter directly in front of the engine with a very short and straight connector from the box to the MAF, and the MAF to the TB.
2) exhaust. The Vette exhaust manifolds are a much better design (almost shorty headers), and they get a true dual exhaust.

 

Almost forgot, HP ratings:
93-95 f-body: 275HP
96-97 f-body: 285HP (from revised y-pipe)

92-96 LT1 Vettes: 300HP