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FE Power Forums => FE Technical Forum => Topic started by: centredautomag on January 15, 2019, 09:40:55 AM

Title: rocker stand shims
Post by: centredautomag on January 15, 2019, 09:40:55 AM: I need to shim my rocker stand .240 is there some shim kit avaliable
Thanks Marc.
Title: Re: rocker stand shims
Post by: Nightmist66 on January 15, 2019, 07:06:50 PM: I made my own. I got some 1/4" steel flat stock and used a drill press, a die grinder, and a large stone to make sure it was flat and even. After I trued it, it came out to about .240", which is what I needed to shim my Harland Sharps with POP shafts, stands, spacers. If you are planning on running studs, I bought some custom length ARP's from one of the vendors on here. I had to neck down the oiling one, as it was a straight 3/8" stud. Here's my homemade junk:

(https://i.postimg.cc/FH7M8WRC/20180902-165845.jpg) (https://postimg.cc/G4ngsjvv)
(https://i.postimg.cc/25WP81n4/20180902-165933.jpg) (https://postimg.cc/KKZ90vqz)
(https://i.postimg.cc/JnWSyRQS/20180903-144227.jpg) (https://postimg.cc/TyCtFMFc)
Title: Re: rocker stand shims
Post by: centredautomag on January 16, 2019, 12:55:49 PM: Very nice job. Time to get the tools out and play. thanks Marc
Title: Re: rocker stand shims
Post by: MrRupp on January 18, 2019, 05:38:59 PM: I know this is a dumb question, but how do you know when you need to shim your rocker stands ?
Thanks Clint
Title: Re: rocker stand shims
Post by: blykins on January 19, 2019, 07:12:36 AM: Quote from: MrRupp on January 18, 2019, 05:38:59 PM
I know this is a dumb question, but how do you know when you need to shim your rocker stands ?
Thanks Clint

When the rocker arm pattern on the valve stem isn't where you want it to be.
Title: Re: rocker stand shims
Post by: Stangman on January 19, 2019, 10:33:59 AM: Hey Nightmist 66 just noticing the single spring. Is the conical spring stronger than a regular spring or is the cam very mild seat pressure wise.
Title: Re: rocker stand shims
Post by: Nightmist66 on January 19, 2019, 07:32:41 PM: The springs are/were a beehive. Very similar to the conicals. They were 155/377open for a custom solid flat tappet that just bit the dust a short time ago. They were set up with different shims/locks for break-in. Had the lightweight shell lifters in it and custom .115" wall 5/16" chromemoly pushrods. Now moving on to a slightly larger solid roller and dual spring setup...
Title: Re: rocker stand shims
Post by: Stangman on January 20, 2019, 01:58:35 PM: Ok thanks, so did the cam go on breakin or just over time.
Title: Re: rocker stand shims
Post by: Nightmist66 on January 20, 2019, 05:11:32 PM: Happened during break-in. Brand new scratch build. 50 mins. run time. :(
Title: Re: rocker stand shims
Post by: blykins on January 20, 2019, 05:16:15 PM: If those were the valve springs that you used for break-in, that's why it wiped....
Title: Re: rocker stand shims
Post by: Nightmist66 on January 20, 2019, 05:32:28 PM: So, have you had experience with these springs and flat tappets for break-in? They were set up with less shim and +.050" locks to keep the pressure down. Is it due to rate on these springs?
Title: Re: rocker stand shims
Post by: blykins on January 20, 2019, 05:53:12 PM: Yes, I use them quite a bit, but I always put a single spring or low pressure dual spring on during breakin. I aim for spring pressures at around 90-100 seat and under 300 open. You were likely still pretty high on pressure.

A .050” valve lock change will only change the spring pressures by 15-18 lbs or so.
Title: Re: rocker stand shims
Post by: Nightmist66 on January 20, 2019, 06:02:46 PM: Seat pressure was around 100psi and I can't remember what the open was.....
Title: Re: rocker stand shims
Post by: blykins on January 20, 2019, 06:10:49 PM: You can multiply your cam lift times the spring rate and add it to the seat pressure to find out.

It would take a lot of change to drop 55 lbs off the seat though.