And they say it's confusing for NON-NCRS folk

[Mark K.]

I've had these two books for years and never noticed the discrepancy. I guess I've always been a C2/Mid-Year/Sting Ray type of guy, but the C1s have interested me as well, just not to the same degree. Anyway imagine my surprise:

Illustrated Corvette Buyer's guide BY MIKE ANTONICK (1983 printing):
page 52 - 1960 Corvette Colors/Options
579 Optional 275 HP, 283 CI Engine
579D Optional 315 HP, 283 CI Engine

Corvette Black Book BY MIKE ANTONICK (1992 Printing):
page 35 - 1960 Options
579 283ci, 250hp Engine (fuel injection)
579D 283ci, 290hp Engine (fuel injection)

Now imagine two Non-NCRS types arguing about the power levels of the 1960 FI Corvettes using these two books as reference. Anyone know when (if) this error was fixed?

[Dennis C.]

The error was fixed when Chevrolet decided...

...the aluminum heads planned for introduction in 1960 were not quite ready for prime time. The horsepower ratings were then devalued to the 1959 stats, but a lot of paper had already been printed showing aluminum heads and the higher power ratings. In any case, conflicting info was out there and it took quite a while to be sorted out. A little like trying to sort out KO wheels for '63...

[Duke W.]

Re: And they say it's confusing for NON-NCRS folk

The 275/315 ratings were finally achieved (and don't forget that most of those SAE gross ratings from that era were highly optimistic) when the cast iron 461X heads were installed on FI engines in 1961. The 461X heads were essentially cast iron versions of the ill-fated aluminum heads from 1960, and they were only installed on the two FI engines.

The advertised CRs also increased to 11:1 for both engines versus 9.5/10.5 for the '59/'60 versions, but as with SAE gross power ratings, CRs were also quite optimistic, and most engines as built were a quarter to half point lower than advertised.

Duke

[GL Anderson]

Re: And they say it's confusing for NON-NCRS folk

Here is a pic of the 1960 aluminum heads. As Duke said they were pretty much the pattern for the 461X heads except for a number of cosmetic differences, the material they are made out of and the screw in studs. Any questions let know and I will pull them out and have a look. GL

[Duke W.]

Re: And they say it's confusing for NON-NCRS folk

Are those pressed in valve guides? What material?

The one on the far right looks very badly worn.

Duke

[GL Anderson]

Re: And they say it's confusing for NON-NCRS folk

Duke these heads have never had valves or guides installed. Just the studs taken out.
GL