Reading the "Rockin' the shaft" article in the July Chevy High Performance magazine, I noticed where "rotating torque" dropped from 75 to 12 ft-lbs when switching to this system. This sounds significant but the article never translates this into horsepower gained/saved. Any ideas on quantifying the performance difference? Thanks for any input!

I've never seen a back to back dyno test of shaft rockers, but have heard that
they can be worth 10-15hp. But this is probably do to a big solid roller that
stresses a regular stud mount rocker, a shaft rocker should get more lift/dur.
to the valve. I've also heard from some engine builders that shaft rockers arnt
worth it??? So who knows, until I watch a dyno run, I'm not sure, but in theory
it should be worth something.

Well, if you were starting from scratch the cost offset would be less than a $100.00, toward the shaft systems.

Lets say the Jesel Sportsman system run $695.00.

A comparable system would consist of:
Crower stainless rockers @ $325.00
ARP 7/16 studs @ $85.00
ARP poly locks @ $85.00
Stud girdle @ $125.00 ish
TOTAL @ $620.00

Oh yeah and add guide plates @ $35.00. That adds up to $655.00.

I am sure that you can use other parts than what I listed, but what I listed is the closest set-up, strength wise that could be considered near a shaft system. Its not just because of a big cam, it really is RPM related and rigity wins.

Shaft systems have numerous pluses over a stud type system.

The main for most would be normal valve lash adjustment intervals like that of a typical hydraulic cam....virtually non existant. Of course, this also depends on what type of cam you are running and how bad you beat on it. I have run the Jesel Sportsman system with 0.600"+ lift mechanical rollers and pegged 8k+ RPM and only adjusted them once a month just to make sure.......but they were dead on everytime.

The natural working harmonics of the valve train are reduced due to the rigidity, which aids in longevity and power production. This open up the point of valve float by a couple hundred RPM and dampends timing scatter at higher RPM's...... :eek:

You can fit them under low-pro valve covers as well, if your tryin to be sneaky...... ;)

Something else that I find nice is that you can remove a 'set' (I&E) from the pedestal without effecting the valve lash. Kinda nice if you were changing valve springs in between rounds at the track or while changing push rods...... :cool:

They can be rebuilt. The adjustment lock is fool proof and will hold the lash. You can get any ratio mixture you want. They will take higher valve spring rates and RPM. And last but not least, they top the bitchen scale. Oh yeah, that's 10-15 hp over roller rockers/studs by them selves. Overall, less friction and better geometry are the biggest plus'.

Bottom line.....for the $40.00 to $70.00 difference, there is no question.........

I have some of the sreet shaft\pedistal rollers from yella terra.I love the things,like the good man said,you can remove them without changing lash adjustments.The ones on my are 1.55 ratio. I paid 530 dollars for them.Check out there web site.

When I said big cam, I ment there's more stress on the valve train, so a shaft
set up will get more lift & duration to the valve - because of the extra rigitity. graemlins/thumbsup.gif

One word: Jesel!

Does Jesel's make an SS shaft-rocker system that will work on Vortec heads(center valve cover bolts)?