Don Terrill’s Speed-Talk

Tuner,
Do you have anything actually useful to add to this thread....or is this your way of getting even.

Warp Speed, I was referring to the 19000+ cam dyno tests that D. Vizard did while contracted to Crane Cams. You have tested a few hundred? Well you have only got about 18000 to go to catch up to DV..... I have NEVER mentioned the number 500,000. Someone else did....I also find the number incredible....

That is why you should get some 25 yr old [ or older ] factory [ or aftermarket ] lifters....& have them re-faced. Then you won't have problems with junk lifters....

And how many cams have you tested, Warp Speed?

If I was trying yo determine the most important valve timing event, I would be trying to find somebody who has tested thousands & thousands of cams.....& did so without any pre-conceived ideas about the results. I only know of one such person who has done this. And he found that IVC was NOT ...

Good article, but..... If the diam of the new 'cartridge' is smaller [ they say the volume is smaller ], then there is more load from the valve springs trying to bleed down the oil....& cause lifter bleed down. If you tighten clearances to reduce bleed down, you also increase the risk of a small...

There is no hard & fast rule & there are plenty of examples of the opposite occurring to what was expected......

Wonder if people really know what they are talking about......when they are recommending a process that they cannot spell correctly.

I have used those lobes for a custom grind & performance was good. No dyno testing, so no figures.
It is well down on lobe lift compared to an Ultradyne/Bullet lobe
#6218. 264 @ 050, 171 @ 200, 340 lobe lift.
UD: 263 @050, 173 @ 200, 370 lobe lift.

Ferrea may make them. 2.11" head, 11/32" stem.

I believe the Pontiac Ram Air 4 intake valve was a tulip valve.

A bush works like a rod brg, needs a pressure wedge & constant oil supply.

Needle brgs need very little oil, marketing hype as far as needle roller lifters go.
Examples of minimum lubed roller brgs: wheel brgs, uni joints, alt brg

I have been running Isky bushed lifters in my GTO now for well over 10 yrs, driven weekly.

I would use the Perf. If it was a 454 or larger maybe the RPM.

Another benefit of the stud girdle is less lost valve motion due to flexing.