0Corvettes by George

I've seen ht and hp on '67 350hp a/c engines, and have always thought both were correct, with the hp suffix indicating 350 hp, a/c, and ps.

I've asked this here before, but cannot find the post.

What's the correct suffix code; or are both correct?

Thanks,
George

JohnZ

L79 without A/C & P/S, or L79 with only A/C or with only P/S = HT

L79 with A/C & P/S = HP

The engine with the HP suffix had the water pump hub pressed to a different dimension than any other small-block (300 or 350hp), thus it had its own dedicated suffix.

0Corvettes by George

Thanks John,
I remembered it had something to do with p/s;
Your response is "crystal".

Would it be possible for you to scan/copy that information from an NCRS tech guide (or like reference) and email it to me?

There is a national flight judge that insists that hp is the only suffix for the 350 hp a/c cars .

Thanks again,
George
geopar@gvtc.com

JohnZ

George -

HP is only correct with A/C when the car also has P/S.

That judge needs to read the 5th Edition of the '67 JG; that information is in the engine suffix chart on page 102.

0Corvettes by George

John,
Very helpful.
Thanks again,
G.

emccomas

Judges continue to learn as well, and hopefully are receptive to new / updated information. Having a copy of the Judging Guide handy when your car is judged is not a bad idea.

And as always, JohnZ is on top of it. Well done John.

rongold

So, what happens when somebody needed a water pump ??? As far as I recall, no pump manufacturer including GM differentiated between a/c, p/s, or a/c & p/s for a replacement pump. How much more or less was the hub pressed on ??? Maybe this is the reason many people have pulley alignment problems.

Powershift

Agree with John's comments. But this info has been known/recognized for many years now. Both here and on the NCRS Tech Site. I own one of the 327/350 HP factory air cars with the HT suffix, and have participated in discussions about this on both boards.

But I guess we still have to continue responding and educating folks.

Another such "issue" is whether the pump to carb fuel line and dipstick tube on the 1967 327/350 HP cars are bare steel or chrome (like the 1966 cars). The latest NCRS Judging Guide address (some of) this issue also.

Larry

JohnZ

Actually, GM never quite figured it out either - they released two different water pumps for Service for '55-'70 small-block Corvettes, and said to compare the pump hub press dimension on the pump being replaced to the new pump to get the right one. They never explained it any further or in any more detail than that, and the difference was 1/4".