Has anyone had experience with grooved lifter bores for use with a solid flat tappet cam? I've heard Comp Cams has a tool for making a pressure fed oil groove within the lifter bores to help oil the cam. What size groove does it make? How much oil pressure is lost or what oil pump should be used? Did it help with camshaft lifespan? UDharold any info?

I use them on all my flat tappet performance stuff. It appears to put oil right where it is needed at the leading edge or opening side of the lifter. (assuming you put the groove on the right side ;) )
I use a hi vol pump & have no issues with oil pressure.
The idle oil pressure appeared about 5-10 lbs lower with a standard pump but came right up with rpm.
I just feel better with the hi volume pump after putting 16 "leaks" in the system.
It is a groove about .040 wide & .010-015 deep. You can adjust the depth with the tool. The .040 is a guess, I would need to measure the cutter if you want it exact.
I cannot say positivily that it helps as I wasn't having a problem before but I run pretty heavy spring pressure on my late model stuff & it sure can't hurt. Makes me feel like I helped anyway :D

Was it easy to do? This seems to me the easiest way to provide oil on the cam lobes at low rpms, the lazer drilled lifters kinda scare me with the hole directly on the face of the lifter.

Bob,
It's very easy to do. the Comp tool make it pretty much dummy proof,,,even I can do it graemlins/clonk.gif
Unfortunately the only time you can do it is when the block is bare,,,unless of course you are one of those rare few that think small pieces on cast iron in your oil help to break in your engine :D

HAPPY NEW YEAR ALL graemlins/thumbsup.gif

Thanks Mike, I guess I'll order the tool. I wouldn't think of doing it with an assembled engine-In fact I'm so anal about engine cleanliness I do an oil filter cut on every oil change just to see what is going on in there, even on the old lady's minivan smile.gif Hope everyone has a great 2004 graemlins/beers.gif