64 Engine internals

[Doug L.]

As long as I am disassembling my engine for rebuild I would like to verify that the internal components are correct. Can anyone tell me the oriignal part numbers for the camshaft and pistons for the 1964 L-84 engine? I assume they are stamped somewhere on the components.

I read in a thread that the solid lifter cars used the Duntov 097 cam until the end of 1963 production, at which time it was replaced with a different cam.

Thanks in advance for any information.
Doug

[William C.]

Re: 64 Engine internals

Generally the can is not stamped from the factory, but there is a casting number on the cam, I believe it ends in the numbers 346. I can't say you will find a number on the pistons, but they are pretty easy to identify if you know anyone who has had one of the solid lifter 327 engines apart. "Duntov" was not used in '64 365/375 hp engines.

[John D.]

Re: 64 Engine internals

Bill Clupper,Learn something new everyday here. Well some days anyhow.
We always called the 30-30 cam the Duntov 30-30. Guess that was just gear head Clem type teminology. JD

[Duke W.]

Re: 64 Engine internals

The number cast into the core is ...347, which is the finished camshaft number; 3849346 is the cam/pin assembly.

The archives are full of information on 327s including the weak points (connecting rods), what kind of parts to use and how to get more low end torque and more top end power at the same time without any effect to external appearance features that affect judging deductions.

You've been here for two weeks. We've been talking about restoring 327s for ten years. No stone has been left unturned.

Try searching "327 LT-1" for starters.


Duke

[Joe L.]

Re: 64 Engine internals

Bill Clupper,Learn something new everyday here. Well some days anyhow.
We always called the 30-30 cam the Duntov 30-30. Guess that was just gear head Clem type teminology. JD

John------


The "Duntov" and the "30-30" were 2 different cams. The "Duntov", aka GM PART #3736097, was used for SHP for 1957-63. Some say, also for the 1956 GM PART #3734077, but I never thought it applied to 1956 (even though the 3734077 and 3736097 have virtually identical specs).

The "30-30", aka GM PART #3849346 was used for 64-65 SHP. The "30-30" referred to the valve lash settings for this camshaft. The "Duntov" cam used tighter valve lash specs.

I think the confusion arises, as it once did for me, because Duntov is closely associated with both cams, even though only one has come to bear his name in the vernacular.

[Joe L.]

Re: 64 Engine internals

As long as I am disassembling my engine for rebuild I would like to verify that the internal components are correct. Can anyone tell me the oriignal part numbers for the camshaft and pistons for the 1964 L-84 engine? I assume they are stamped somewhere on the components.

I read in a thread that the solid lifter cars used the Duntov 097 cam until the end of 1963 production, at which time it was replaced with a different cam.

Thanks in advance for any information.
Doug

Doug------


Briefly, the camshaft should have the "347", "9347" or "3849347" cast between the lobes. If it does, it's an original camshaft or an original replacement. This cam was discontinued about 40 years ago, so if it's an original replacement, it had to have been done a long time ago.

The original (or original replacement) pistons will be easy to identify. On the underside there will be a "GM" embossed along with a forging number. I don't recall what the forging number was for these pistons but it was a 7 digit number that began with "38". In any event, if you find a "GM" and a "38xxxxx" number embossed on the bottom of the pistons and the pistons are of the domed type, then you have original or original replacement pistons. There is no way to discern an original piston from a GM SERVICE piston of the period UNLESS the SERVICE piston is a +0.030" oversize or greater. In that case, it pretty much has to be a SERVICE piston.

By the way, none of the above parts remain available from GM.