Suburbazine

I will add, the picture doesn't show the disturbing part. A lot of the 90 degree edges on the cam (the lobes in particular) have random pitting/chipping. These are non-contact surfaces, so this indicates corrosion or stress fractures. There's no rust and it looks like a crappy machining job, except when the cam was new all the edges were razor clean.

So I will hold to my original assessment, the cam was a crap blank from Comp when it was made. I don't have the $$$ to get it sent through a metallurgical analysis right now, but I can't imagine the results would be much different from what I know now.

gagliano7

This has been all over Ls1tech for the last couple of years. Seems like every month another couple come up.

Vortec350ss

iTrader: (20)

Do you know which lobes you had and which springs you were running?

TX Tahoe Z71

iTrader: (28)

You're right, did some reading, seems not to be so uncommon

Gadgetized

iTrader: (9)

The thing that really has me wondering is that the cam wears and the lifters don't. There is much more surface area to the cam than there is the lifter, and the lifters never wear and the cam always does. There is just as much pressure up on the lifter as there is down on the cam. I can't believe that they are properly heat treating the cams before they leave.

1FastBrick

iTrader: (17)

The cores are already heat treated prior to grinding them to spec.
The main journals are ground after heat treating.

If you heat treat again after grinding the lobes, it will distort the cam shaft.

Comp does not stock the LS cores. They buy them from other vendors in the industry who do depending on demand and grind as needed.

Gadgetized

iTrader: (9)

I didn't know that, I assumed they were heat treated after they were cut. Good info.

Suburbazine

I was running TEA dual valve springs for .650 lift. Here's one that broke a while back:


Here's the cam sheet:

stock48

iTrader: (16)

That lift looks pretty aggressive for the duration. How much open spring pressure was it running? Could be a hardening problem, too much spring, too aggressive of lobe, or combination of the 3. Just pulled down my Nova engine to freshen after 3 years and my 218/.570 JFR/Isky is in perfect shape.

Vortec350ss

iTrader: (20)

Those look like the EPS lobes... Oy...

The EPS lobe is fairly similar to the comp LSL from what I can tell. For what its worth Tooley loves the LSL. Its the intake lobe on almost all of his cams.