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Aubrey N Bruneau · 08-19-2007, 11:23 PM

Has anybody here, other than myself, ever used the solid version of the Schubeck lifter ?
SURELY there HAS to be SOMEONE who has them in a 375HP 396 or the like ? no ?
I've been running mechanical cams in various engines, since 1977. All came from the manufacturer with a recemmended lash setting... generally in the .016" - .026" range. The "rule" as I have discussed on hundreds of occasions, is that you can tighten as much as .004" to MAYBE .006", or loosen .002" - .004".
I can't help but become concerned that if a person were to tighten lash on a mechanical lobe that has say, a .020" "ramp" off the base circle, to .004" or .006"..... that besides the obvious loss of cylinder pressure at anything below 6000 RPM, there would also be a concern of the valve practically never sttling on the seat.

Would take a different lobe design for sure.
On a hydraulic profile.... ABSOLUTELY.... if you were to back the lash to even .010", it would smash the hell out of everything.
On an even remotely traditional mechanical flat tappet cam lobe, there HAS to be some form of mechanical "cushion". Tight-lash cams are the latest though. Some have as little as .012". But that's as tight as I've ever seen.

"Starter to turn the engine over when setting valves" ?????????!!!!!!!!!!!!!

08-19-2007, 11:23 PM	#42
Aubrey N Bruneau Member Join Date: Sep 2003 Location: South Eastern Alberta, Canada Posts: 311 Likes: 6 Liked 7 Times in 3 Posts	Re: Schubeck Lifter Update Has anybody here, other than myself, ever used the solid version of the Schubeck lifter ? SURELY there HAS to be SOMEONE who has them in a 375HP 396 or the like ? no ? I've been running mechanical cams in various engines, since 1977. All came from the manufacturer with a recemmended lash setting... generally in the .016" - .026" range. The "rule" as I have discussed on hundreds of occasions, is that you can tighten as much as .004" to MAYBE .006", or loosen .002" - .004". I can't help but become concerned that if a person were to tighten lash on a mechanical lobe that has say, a .020" "ramp" off the base circle, to .004" or .006"..... that besides the obvious loss of cylinder pressure at anything below 6000 RPM, there would also be a concern of the valve practically never sttling on the seat. Would take a different lobe design for sure. On a hydraulic profile.... ABSOLUTELY.... if you were to back the lash to even .010", it would smash the hell out of everything. On an even remotely traditional mechanical flat tappet cam lobe, there HAS to be some form of mechanical "cushion". Tight-lash cams are the latest though. Some have as little as .012". But that's as tight as I've ever seen. "Starter to turn the engine over when setting valves" ?????????!!!!!!!!!!!!! __________________ Aubrey N Bruneau 6409 C/S 62 BelAir sport coupe, 409 HP 409 Last edited by Aubrey N Bruneau; 08-19-2007 at 11:26 PM.