Why does the 97 LT1 fbody engine rate @ 285 hp and the other years at 275 hp .... what did they change to get that - does anyone know???

 

The dual cat setup on the 97s is supposedly good for that additional 10hp...

 

so the engines are identical??

 

They also had a little different head castings, which flowed slightly better, around 3% I've heard.

 

the greg97 thats exactly like my car in your pic and I've got basically the same set up at you - except mines an A4. I work in morgantown right down the road from you ...

 

Why would they have different head castings? First I've heard of that...JMHO

 

The 96-97 f-bodies had dual catalytic converters, which supposedly upped the power by 10hp. I've never head of a difference in the head castings, other than the Impala LT1 had iron heads and the f-body LT1 had aluminum.

 

I don't know why they would, but they do. They are a lighter casting with slightly better flow on the intake I beleive. There are two different LT1 head castings, I think the numers are #561 & 571.

Wayne, sent you a pm.

 

never heard the head casting thing either...the dual cats is basically 10 hp on paper ...never saw any noticable differance in performance from any other years

 

i figured this would have been discussed quite a bit in the past ...
looks like ive started some trouble....

 

Do a search on it, it's been discussed. Lloyd Elliot has mentioned the difference a few times, he actually prefers the older castings though for extensive porting because there is more material to work with in those heads, you can't port the lighter castings as much. The change may include 96's as well but I know I've heard they are different on 97's. I'm not trying to say there was any huge difference in them but they are different.

 

I have heard that the 96-97's have a different cam.

 

can anyone answer this?? why is the corvette LT1 rated @ 300 hp?? whats different between those two (fbody, corvette)?

 

Intake & exhaust

I've also heard about the different castings...

 

thats it?? no different programing for a more aggressive car, or anything else?