1962 300HP camshaft

[Kenneth F.]

Would someone have specifications, and possibly a reliable vendor for the 1962 300 H.P. camshaft?
A vendor advised Melling #C-400-P but I believe it to be more correct for a 350 H.P. with an idle rougher than I care for. The C-400-P has specs for cam lift of.298 for int. and exh. and SAE duration of .291 for int. and exh.

[Timothy B.]

Re: 1962 300HP camshaft

Kenneth,

I think the archives will give you the information you seek. The general consensis is to use the 1967 and later 3896929 cam. The specs are very close to the original cam #3733431. Try this link for more info on the camshaft.

https://www.forums.ncrs.org/showthre...shaft&uid=7404

[Duke W.]

Re: 1962 300HP camshaft

As stated the '62 327/300 camshaft that was the '57-'66 "base engine" camshaft (and also used in optional hydraulic lifter engines other than L-79) was replaced by the 3896929 in '67, and the ...929 is the replacement cam for that discontinued/obsolete camshaft back to '57.

It has very similar specs and milder dynamics. You won't be able to tell the difference from the original, but it's easier on the valvetrain.

Go to www.napaonline.com and use the online catalog cross reference to find the Federal Mogul Sealed Power OE replacement, which costs less than sixty bucks.

Duke

[Kenneth F.]

Re: 1962 300HP camshaft

Hello Duke and Timothy, Napa lists #SEPCS274 camshaft as "OEM replacement" with specs of int. lift .260, exh. lift.273,
int. duration .194 exh. duration .203
I do not understand a lot about camshaft specs, but it appears there is a signficant difference between the two camshafts, in lift and duration. I can understand why there will be less valve train stress with the 300 H.P. camshaft.
I really appreciate the excellent advice.
Ken

[Duke W.]

Re: 1962 300HP camshaft

The '57-'66 base engine camshaft is 196 deg. duration at .050" lifter rise with .26581" gross lobe lift, which is not that different than the ...929. (See below for why the exhaust duration is longer.)

It is a "single pattern" camshaft - same lobe on both sides.

The "ID number" on this camshaft is 3732798, which is the finished camshaft part number. The "assembly" of camshaft and indexing pin was sold over-the-counter under part number 3733431.

Even if you could find one of these obsolete camshafts I would not recommend using it. It was designed for the 283 "small port" heads and before Chevrolet had a good understanding of valve train dynamics.

The ...929 was designed with substantial understanding of valve train dynamics that Chevrolet Engineering gained in the early sixties and for the lower E/I flow ratio of 327 "big port" heads. That's why it has longer exhaust duration.

Trust me. Use the Sealed Power CS-274, which is built to the GM print of the 3896930 GM finished camshaft (...929 camshaft/pin assembly).

If you want more top end power and useable revs without loosing the OE low end torque and smooth 500 RPM idle, "massage" the cylinder heads (see archives) and install the cam retarded 4 degrees from the OE indexing.

If you're rebuilding the entire engine, I'd also strongly recommend replacing the weak OE rods with the new Eagle SIR5700SP rods (see archives).

Duke

[Joe L.]

Re: 1962 300HP camshaft

Hello Duke and Timothy, Napa lists #SEPCS274 camshaft as "OEM replacement" with specs of int. lift .260, exh. lift.273,
int. duration .194 exh. duration .203
I do not understand a lot about camshaft specs, but it appears there is a signficant difference between the two camshafts, in lift and duration. I can understand why there will be less valve train stress with the 300 H.P. camshaft.
I really appreciate the excellent advice.
Ken

Ken-----


I would use the Sealed Power camshaft that Duke recommends. I think you will be 100% happy with it.

Want to use a GM cam? No problem. Order up a GM #14060651. You will be 100% satisfied with it, too. It will be more expensive, though. List price is almost 300 bucks, but you should be able to buy one for about 175 bucks.

[Kenneth F.]

Re: 1962 300HP camshaft

Hello Duke and Joe, Your information is most helpful. This is much easier than changing the parts with the engine in the car. I would have never arrived at the same conclusion without your help. I will do some archive research on the rods.
Ken