Billet cams and lifter supply

[nolongerracing]

Nitride cast cam. 200/400 spring pressures. The most common issue. Tool steel or Shubeck lifters. Didn't matter. Oil, didn't matter. I was told by a cam salesman that if you got a year out of a cam like this you were "doing good". Thats why we switched to steel cams. The problem continues.
Going back to "pure stock" rules will not help. Just lost a few lobes in a stock rebuild 350 Chevy. We did everything we could for break in. Oil, additive, 1.2 rockers, 1/2 hour run time, etc, etc,. Cores are junk, lifters are junk, oil is junk, heat treat is junk.
Hate to say it.. Seems to start with the EPA!! We can't build what we need!!

[GTX JOHN]

I still run the old Isky cams that I got from them in the
80s and 90s and actual Hydraulic Schubecks from 20 =
years ago. Some same old valve springs 165 seat and some
beehives on a couple cars. Never a problem I still can run 1+
under (Some of our cars even well more) when I want it too.
Engines in a couple cars are 8 plus years of regular racing. Plus
with just only one valve job.

I am sure I am a tenth or two behind the curve
of the top dogs. However, I am not spending a lot of money to race
and I still win more heads up than I lose. NO valve train issues.

[Stan Weiss]

Originally Posted by nolongerracing

Nitride cast cam. 200/400 spring pressures. The most common issue. Tool steel or Shubeck lifters. Didn't matter. Oil, didn't matter. I was told by a cam salesman that if you got a year out of a cam like this you were "doing good". Thats why we switched to steel cams. The problem continues.
Going back to "pure stock" rules will not help. Just lost a few lobes in a stock rebuild 350 Chevy. We did everything we could for break in. Oil, additive, 1.2 rockers, 1/2 hour run time, etc, etc,. Cores are junk, lifters are junk, oil is junk, heat treat is junk.
Hate to say it.. Seems to start with the EPA!! We can't build what we need!!

If the EPA is the problem than making the parts outside the USA would fix it.


How many vehicles today run OHC on bucket setups? Which is nothing more then the cam against a flat tappet



Stan

[Rory McNeil]

Originally Posted by Stan Weiss

If the EPA is the problem than making the parts outside the USA would fix it.


How many vehicles today run OHC on bucket setups? Which is nothing more then the cam against a flat tappet



Stan

Totally different situation. The OHC engines with buckets have no rocker arms, lifters or pushrods, so the valve springs are generally much less tension, since the weight of the valve train is so much lighter. Even more so with a 4 valve head, since the valves are considerably smaller, as are the spring diameters and retainers. Also, the buckets do not need to rotate like a flat tappet cam, and the cam lobes are not ground on a taper, to promote rotation.

[Stan Weiss]

Originally Posted by Rory McNeil

Totally different situation. The OHC engines with buckets have no rocker arms, lifters or pushrods, so the valve springs are generally much less tension, since the weight of the valve train is so much lighter. Even more so with a 4 valve head, since the valves are considerably smaller, as are the spring diameters and retainers. Also, the buckets do not need to rotate like a flat tappet cam, and the cam lobes are not ground on a taper, to promote rotation.

Let leave 4v DOHC out of this and just look at 2v Single OHC. While there is no rocker arm or pushrod the bucket replaces the lifter and is traveling at valve velocity / acceleration while the lifter would be traveling slower.


Stan

[pmrphil]

But the oil can "puddle" on the top flat area of the "lifter", how long do you think it could last upside down?

[Mike Gray]

Finally, just received my new coated PPPC lifters.

[ProfessorRock]

Just curious Mike ,asking for a friend, how much did the get for coated lifters. DLC?