The '71-'72 Horsepower "Cliff", what happened?

[Terry M.]

Re: The '71-'72 Horsepower "Cliff", what happened?

I remember in 2008 Chevrolet made a big deal out of the Z06 achieving 505 hp using the then-new SAE standards. they were quite proud of that. Your 638 is nothing to sneeze at either. Joe Lucia is absolutely right, but I believe we are going to see another horsepower cliff either next year or very soon.

[Michael J.]

Re: The '71-'72 Horsepower "Cliff", what happened?

I remember in 2008 Chevrolet made a big deal out of the Z06 achieving 505 hp using the then-new SAE standards. they were quite proud of that. Your 638 is nothing to sneeze at either. Joe Lucia is absolutely right, but I believe we are going to see another horsepower cliff either next year or very soon.

You got that right Terry, all the "stars" are aligned to push us off that cliff too, better enjoy things like we did in '71.

[Terry M.]

Re: The '71-'72 Horsepower "Cliff", what happened?

You got that right Terry, all the "stars" are aligned to push us off that cliff too, better enjoy things like we did in '71.

Yep. We are in store for another "It was the best of times, and we didn't even know it" moment. I think it is kind of neat to have lived through two of those for cars.

[Jim T.]

Re: The '71-'72 Horsepower "Cliff", what happened?

Duke I am very fond of my 96 LT4's performance, what would you estimate the horsepower of the LT4 engine in 1970 horsepower ratings?

[Jim T.]

Re: The '71-'72 Horsepower "Cliff", what happened?

Duke I am very fond of my 96 LT4's performance, what would you estimate the horsepower of the LT4 engine in 1970 horsepower ratings?

[Duke W.]

Re: The '71-'72 Horsepower "Cliff", what happened?

About 375 honest, but they probably would have claimed 400 since the SAE gross ratings of the sixties were overstated by typically ten percent or more.

If you put a typical Flint-built L-79 on a lab dyno and tested it honestly to the SAE gross spec it would be about 300 @5500. Massaging the heads and making sure the actual CR is at least 10.5 will get pretty close to the claimed 350 gross. As-built the production heads have serious air flow restrictions, which are pretty easy to improve on. We've known how to fix them for over 40 years, but most guys still think there's something wrong with the cam.

Duke

[George J.]

Re: The '71-'72 Horsepower "Cliff", what happened?

The age of high performance was not THEN, it's NOW!

Joe,
I would say an age of high performance has more to do with how they were pushing the envelope of the day. The 30-30 cam was really out there as far as a street cam. And look at what Zora and the others were trying in the back room. I am sure there is not as much secret, off the books, stuff going on today. That, to me, is the magic of that era. Of course, the engines of today are a masterpiece of power, reliablity, etc., and I wouldn't trade them for the older stuff in my daily driver.

George