Question For Joe Lucia/Duke or anybody on Camshaft Knowledge

[Larry E.]

Question/Just Curious>Can GM L-46/L-82 camshaft, GM #3896962 be put in a Base L75 (1966) W/O
any engine modifications? Would there be any problem with piston/valve clearance or the stock valve springs?
Toying with this idea. Thanks in advance>Larry

[Edward J.]

Re: Question For Joe Lucia/Duke or anybody on Camshaft Knowledge

Larry have you tried your local machine shop to see if anyone makes the correct replacement camshaft, they should be able to look up the factory spec. and see if there is a crossover for it. I recently ran into this on a seal power camshaft for a 63 Fuelie which is no longer available.

[Duke W.]

Re: Question For Joe Lucia/Duke or anybody on Camshaft Knowledge

All Corvette small blocks of the era used the same valve springs regardless of camshaft, 3911068, Sealed Power VS-677.

This cam is very similar to the L-79 cam. The biggest difference is that the IPOML is 114 deg. ATDC. On a 327 it should be installed with an adjustable truck roller chain (made by Cloyes, about 25 bucks at NAPA) four degrees advanced to bring the IPOML back to 110, same as the L-79 cam.

Replacing the base cam with the L-79 or L-46/82 cam was a popular option back in the day, and it essentially turns a base engine into a L-79/46. The idle gets more "attitude", 750 @ 14-15" and you loose some low end torque, but gain top end power and revs. Most I know who made the conversion were very happy with the results.

I like this cam better than the L-79 cam because it was designed a few years later and benefited from Chevrolet's valve train dynamics research with the Optron machine. It has refined lobe dynamics and even though both lobes have the same .050" lifter rise duration, they are actually different as you can see from the slightly higher gross lift of the exhaust lobe. The L-79 uses the same lobe on both sides.

The OE 300 HP pistons or equivalent have plenty of valve clearance with this cam.

Duke

[Duke W.]

Re: Question For Joe Lucia/Duke or anybody on Camshaft Knowledge

Larry have you tried your local machine shop to see if anyone makes the correct replacement camshaft, they should be able to look up the factory spec. and see if there is a crossover for it. I recently ran into this on a seal power camshaft for a 63 Fuelie which is no longer available.

A local machine shop is the LAST place I would turn to for camshaft advice. Most have their favorite hot rod cams and know little or nothing about OE cams.

The '62-'63 340/360 HP engines used the "Duntov cam", Federal Mogul CS-113R, and AFAIK it's still available, but I recommend the LT-1 cam to replace it (CS-1145R). A recent thread reports difficulty finding a L-46/82 cam (CS-1095R), and Joe Lucia reported that it's still available from GM, 3896962

Duke

[Joe L.]

Re: Question For Joe Lucia/Duke or anybody on Camshaft Knowledge

Question/Just Curious>Can GM L-46/L-82 camshaft, GM #3896962 be put in a Base L75 (1966) W/O
any engine modifications? Would there be any problem with piston/valve clearance or the stock valve springs?
Toying with this idea. Thanks in advance>Larry

Larry------


No problem, whatsoever, installing the 3896962 in an L-75 (or, an L-48 for that matter). As a matter of fact, some currently manufactured GM crate Gen I small blocks are, essentially, an L-48 with 3896962 camshaft.

[Larry E.]

Re: Question For Joe Lucia/Duke or anybody on Camshaft Knowledge

Joe/Duke>>Thanks for the great info. Now>Would GM Lifter #
5232720 be the best for this cam? If not what would? Thanks-Larry

[Duke W.]

Re: Question For Joe Lucia/Duke or anybody on Camshaft Knowledge

It's my understanding that there is only one Gen 1 SB/BB hydraulic lifter manufacturer, so whatever GM sells is likely the same as everyone else, so shop around.

Duke

[Joe M.]

Re: Question For Joe Lucia/Duke or anybody on Camshaft Knowledge

Thank you for your order. Part ~844 CS1095R cam is discontinued. Speed Pro has not offered any replacement item. Your backorder for this item has been canceled. If you have any questions please call us at 1-800-345-4545 and speak with a tech sales representative. We apologize for the inconvenience.
Jeg's Customer Care