Reply to "#1493 motor update"

A custom grind camshaft will have an ID number stamped or ground into the face of the front bearing lobe.

You need to strip the engine down to see it though.

Personally I am not a fan of "roller camshafts". They carry a lot of additional weight, i.e., rotating mass and the only way to deal with that is with increased valve spring pressures.

I personally would prefer a lighter and less complicated (less parts) to the lifter assemblies.

A lot of people have just good things to say about hydraulic roller lifter camshafts.

If it was me and I was so unsure about the existing camshaft I would replace it with a solid lifter grind.

You already mentioned that your engine has lifter bushings installed. That usually is done for oil restriction to the valve train for engines that are intended to be run over 7,000rpm.

It is controversial for sure and I'm not looking to open that debate up again.

I don't know if you can run a hydraulic camshaft now because of the bushings.



The benefit to the roller cam, if all the specs are the same as a regular flat lifter cam, is that the lifter lobe ramp is steeper on the roller and opens the valve faster than a flat lifter camshaft can.

That gives the engine more "energy" and makes it feel peppier.

In the past roller lifter valve trains have had issues with longevity in street driven engines.
Durability has been vastly improved though since "Detroit" has gone to them in regular production vehicles.

Apparently some of that technology has trickled down enough to make aftermarket cams much more dependable.

One issue with aftermarket camshafts though is so many components are being made "offshore" for the cam companies that quality control, at least in my mind, can be a concern.

Sounds like you are using CHI heads which really have a great reputation.

I do know that some of the older "original Ford heads" needed to be machined for lifter assembly clearance.

That shouldn't be a matter to you though. Your engine is built and running.

My solution would be to change the cam to something I new.

The main concern on ANY CAMSHAFT now for LONGEVITY is going to be the spring pressures.

The higher the pressures, the shorter the life expectancy is going to be.

Again, you don't even know what the spring pressures are in your engine but with solid roller lifters they could be over 400 pounds open.

You are really relying on the quality of the spring with pressures that high.

I like to stay 350 or under. That is usually a dual spring, one inner, one outer, with a dampener.