Originally Posted by shaffe
Dumb question possibly, someone please correct me if I am wrong.
I see here that even though engines were identical( in the 70 -74 cars), the Vette was rated higher. IIRC wasn't the highest rated ( or advertised HP) corvette 435HP
So if the Corvette had to have the highest HP how did the 70 Chevelle get away with its advertised 450HP in the LS6 454
Apples 'n oranges...
The 435hp L71 427 '67-'69 Corvette was the "highest Factory-RATED" Corvette...but NOT the most powerful. "Ratings" and "actual" didn't always correlate. The L-88 and ZL-1 Corvettes were rated 430 hp...at something like 5200 rpm, well below their 6000+ power peak. And the L71 (also available with aluminum heads as option L89 in '69) was a Corvette-only option.
The '70 LS6 454-450hp engine offered in the Malibu was NOT offered in the Corvette.
The LS6 454-425hp Corvette engine of 1971 was essentially a lower compression L-88 with 27 more cubes.
In early '70 literature, mention was made of an LS7 Corvette engine, a 454" version of the high-comp L-88 rated at 460hp, but emissions issues meant it never made production...