Quote:

---

Funny how people overlook the flaws on the Chevy head and the millions spent on R&D to correct them over the last 4+ decades.

Do max effort "chevy" heads retain their sloppy chambers, or weak rockertrain, or lousy ports (among other things)...........I think not. If it comes down to FACTORY iron, I'll take a HEMI over a 427.

We all see how the development of the "99" prostock head does in the power making department. Is it radically different than a stock HEMI??? Of course......but so are the chevy heads compared to a stock iron rec. port head.

ALL factory performance heads had strong points and drawbacks, it's the aftermarket that has been kind to the chevy and ford deals for economic reasons that has led to their capabilities. As was mentioned in a pervious post, lets go back in time to 1970 parts and see how the chevys and fords would do without their non-stop, aftermarket development against the HEMI.

If I recall, they did't fare to well before the heavy hands of NASCAR and the NHRA put the HEMI to bed.

---

another correct answer....

No one has mentioned that Chevy designed the "mystery motor" over several years and still it had a hard time outrunning a Hemi(10 years of NASCAR and NHRA sanctions made it possible). The Hemi was on the drawing board and won Daytona in less than a year(11 months?) from what I remember...
using a (modified)passenger car blocks and old 392 Hemi head technology. Not bad for a motor that was thrown together...
and now (almost)50 years later copies of them are making 7,000+ horsepower or 14 hp pci...how can that be considered inefficient

http://en.wikipedia.org/wiki/Chevrolet_Big-Block_engine