Originally Posted by Mbrown
I am setting up the valve train on a 540 and wanted some opinions on what to do. I have always used B3 shaft relocation kits, but now I am having second thoughts. I want to make it clear that i am not bashing Mike or his products. I am just having trouble with this application.
I have measured valve lift with checking springs and the actual springs. I did all checks with 0 lash to help eliminate human error. Lobe is .465" . The rocker arms are advertised as 1.7 ratio. My springs are 255#'s on the seat and 660#'s at .770 lift.

With shaft relocation kit, lift at valve was .771 with checking spring. The lift at the valve with the real spring was .712". That is A LOT of deflection. Scrub pattern was .045-.050" wide and centered. I am not happy having that much deflection. So I decided to check without the shaft relocation kit.

Without the shaft relocation shims, the lift at the valve with checking springs was .790". The lift at the valve with the real springs is .776". The scrub pattern is huge though. .090-.100", but centered.

My question is, do I run with or without the relocation shims? I have considered machining new hold downs that would help stabilize everything when using the relocation kit. Any suggestions?



I've just been through the same observation when changing to a different flat tappet cam using the B3 setup. I noticed a fair amount of fretting/walking marks on the shims so i checked side to side flex at the hold down stud and it was around .0015-.002. and this is with 150# seat pressure and .620 lift.

I switched from using the B3 kit with Hughes rockers to a T&D rocker assembly. The pattern isn't quite as centered (very close to center though) now, but is as narrow and it is much closer to full lift with flex at hold down stud gone now.

I have another engine with roller and Jesel 1.7 individual shafts and @.799 theoretical lift, it only loses about .015 to actual lift at retainer w/ 350# seat springs....scrub was minimal, but i don't recall actual width.

I think the B3 kit is a good idea, but it has spring pressure and lift limits.

Last edited by Harry's Taxi 2; 03/17/24 06:57 AM.
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