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AlanPetersJr. 07-14-2014 05:42 PM

396 Cam question
 
Hi guys, just for my own curiosity, what camshaft does the 65 425 h.p.
396 use? I know that the big Chevy, the Vette, and the Z16 were rated at
425 h.p. For some reason I thought they used a hyd. camshaft. Also, how does
the 65 396 Vette fit A / Stock? Like i stated I am just curious.
Thanks in advance, Alan jr.

Superfan1 07-14-2014 06:17 PM

Re: 396 Cam question
 
Quote:

Originally Posted by AlanPetersJr. (Post 437880)
Hi guys, just for my own curiosity, what camshaft does the 65 425 h.p.
396 use? I know that the big Chevy, the Vette, and the Z16 were rated at
425 h.p. For some reason I thought they used a hyd. camshaft. Also, how does
the 65 396 Vette fit A / Stock? Like i stated I am just curious.
Thanks in advance, Alan jr.

According to the NHRA Classification Guide, the '65 Vette was factory rated at 425 HP, but, with OEM heads, it is NHRA rated at 375 HP, which gives it a factor of 8.06 which makes it a "natural" A/S car (8.00 - 8.49). With replacement heads it is NHRA rated at 385 HP which gives it a factor of 7.85 which makes it a "natural" CC/S car (7.50 - 7.99).

X-TECH MAN 07-14-2014 06:18 PM

Re: 396 Cam question
 
Quote:

Originally Posted by AlanPetersJr. (Post 437880)
Hi guys, just for my own curiosity, what camshaft does the 65 425 h.p.
396 use? I know that the big Chevy, the Vette, and the Z16 were rated at
425 h.p. For some reason I thought they used a hyd. camshaft. Also, how does
the 65 396 Vette fit A / Stock? Like i stated I am just curious.
Thanks in advance, Alan jr.

The original Z-16 1965 Chevelle (396) used a Hydraulic cam and was rated at 375 HP from the factory. The 65 396/425 Hi HP Vette used the same SOLID LIFTER cam as a 427/425 Vettes, Camaro, Big cars, and later 396/375 HP(1966 and up) Chevelles. It had .520 lift. Superfan 1 is correct on the later HP ratings with the replacement parts.

Alan Nyhus 07-14-2014 06:34 PM

Re: 396 Cam question
 
Alan, the '65 396-425's (Corvette and full size Chevys) had a mechanical lifter camshaft with .497/.503 lift. This was a different camshaft than the '66 and later 396-375's and 427-425's (.520/.520).

The '65 396/375 was only available in the Z16 Chevelle. That motor was virtually the same as the '65 396-425's with the exception that it used a hydraulic cam (.461/.500). Most people assume the '65 396-375 Z16 is an L78, which it isn't. It's actually an L37.

Hope this helps. -Al

Jeff Niceswanger 07-14-2014 08:11 PM

Re: 396 Cam question
 
What was the difference between the 1st design and 2nd design L-88 camshafts...I had that 1st design in a 427/425.69 RS Z-28( street car)
.To this day, I prefer the rattle of that old motor over any other camshafts....I'm sure different grinds made more power, but that thing sounded nasty....

Alan Nyhus 07-14-2014 08:45 PM

Re: 396 Cam question
 
Quote:

Originally Posted by Jeff Niceswanger (Post 437893)
What was the difference between the 1st design and 2nd design L-88 camshafts...I had that 1st design in a 427/425.69 RS Z-28( street car)
.To this day, I prefer the rattle of that old motor over any other camshafts....I'm sure different grinds made more power, but that thing sounded nasty....

The 1st design L88's....'67 and '68 (even though NHRA doesn't recognize the '67)....were .562/.584 lift. The second design ('69) cam was a .560/.580. Even though the lift was close between the two, the profiles were quite a bit different. -Al

Dwight Southerland 07-15-2014 07:47 AM

Re: 396 Cam question
 
Quote:

Originally Posted by Alan Nyhus (Post 437886)
Alan, the '65 396-425's (Corvette and full size Chevys) had a mechanical lifter camshaft with .497/.503 lift. This was a different camshaft than the '66 and later 396-375's and 427-425's (.520/.520).

Same camshaft, just a clerical difference. If you look at the original (1965 version) of the NHRA Tech Bulletin, the part number is listed for the camshaft and it is the same as all the later L72 and L78 engines - 3863143 with a casting number of 3863144. If you research any and all of Chevrolet's documentation, whether it is parts manuals, production specifications or whatever, the 1965 engine used the same camshaft as every other 396 solid lifter engine built between 1965 and 1969 with lift specifications of .520"/.520". Chevrolet power manual lists the specifications of the same part number camshaft as "net lift" of .500" with lash settings of .024" intake and .028" exhaust. Maybe Chevrolet provided NHRA with net lift numbers in 1965, who knows. Regardless, the .497"/.503" numbers are in the 'Guide and we have to live with it.

Also, the hydraulic camshaft used in the 396-375 Z16 Chevelle is the same camshaft used in the 396-350/360 hp engines and 427-385/390/400 hp engines in 1966-1969, again with slightly different clerical numbers.

Alan Nyhus 07-15-2014 08:14 AM

Re: 396 Cam question
 
Quote:

Originally Posted by Dwight Southerland (Post 437916)
Same camshaft, just a clerical difference. If you look at the original (1965 version) of the NHRA Tech Bulletin, the part number is listed for the camshaft and it is the same as all the later L72 and L78 engines - 3863143 with a casting number of 3863144. If you research any and all of Chevrolet's documentation, whether it is parts manuals, production specifications or whatever, the 1965 engine used the same camshaft as every other 396 solid lifter engine built between 1965 and 1969 with lift specifications of .520"/.520". Chevrolet power manual lists the specifications of the same part number camshaft as "net lift" of .500" with lash settings of .024" intake and .028" exhaust. Maybe Chevrolet provided NHRA with net lift numbers in 1965, who knows. Regardless, the .497"/.503" numbers are in the 'Guide and we have to live with it.

Yep...it's probably one of those odd things that just never got corrected in the Tech Bulletin. -Al

james schaechter 07-15-2014 08:27 AM

Re: 396 Cam question
 
Quote:

Originally Posted by Alan Nyhus (Post 437917)
Yep...it's probably one of those odd things that just never got corrected in the Tech Bulletin. -Al

Bob Gipson made that case with NHRA and they stick with the lower lift cam. That is what he has in his 65 vette A/Stick. Fun car and it is for sale.

Run to Rund 07-15-2014 08:51 AM

Re: 396 Cam question
 
I agree that the first design L88 cam had a great sound. I can't get to my chevy power books right now but they showed the profiles, etc. iirc, it was about 264 deg. at .050" and rated duration was around 360 deg.

Dwight Southerland 07-15-2014 11:01 AM

Re: 396 Cam question
 
Quote:

Originally Posted by james schaechter (Post 437918)
Bob Gipson made that case with NHRA and they stick with the lower lift cam. That is what he has in his 65 vette A/Stick. Fun car and it is for sale.

Jim - I made that case, too, with lots of Chevrolet documentation but no takers in Glendale.

X-TECH MAN 07-15-2014 01:31 PM

Re: 396 Cam question
 
OK....My bad. I haven't looked at this stuff in about 13 years. The 65 396 lift is .497/.503. Just dug my old books out a bit ago to be sure. I had it right on the Z-16. Guess I need to keep the books close by the computer. Sorry.

Dan Bennett 07-15-2014 03:41 PM

Re: 396 Cam question
 
The 65 Corvette cams used a grooved journal/bearing but the later cams were flat. I'm sure this has nothing to do with cam specs but may have caused a difference in part numbers.

Alan Nyhus 07-15-2014 03:53 PM

Re: 396 Cam question
 
Quote:

Originally Posted by X-TECH MAN (Post 437950)
I haven't looked at this stuff in about 13 years. The 65 396 lift is .497/.503. Just dug my old books out a bit ago to be sure.

Those old red covered Classified Guides and Technical Specifications are a wealth of info, aren't they? You can find some odd trivia in there, for sure.

Good stuff....... :) -Al


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