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Mon Aug 25, 2014 9:58 pm

I was setting up rocker side play the other day using an EMPI shaft kit. I wish I would have had more shim thicknesses, so I looked into a hardware catalogue and found some shims that have the same dimensions. Are .005s too thin to use safely on rocker assemblies, or shoud I go no smaller than .010? I can get a pack of 25 of whatever size for eight dollars.

Are there better shim selections from another company? EMPIs came with .017, .032, and .059. Those measurements were taken after I sanded down the stamped edges.

Mon Aug 25, 2014 11:20 pm

Aircoolednet and cb-performance carry them but I think most kit's just have 3 sizes in them. .005" would be nice so they could be dialed in better. I think they would work.

Tue Aug 26, 2014 6:16 am

What catalog were you looking at?

Tue Aug 26, 2014 11:25 am

I had to sand one of the thicker shims down a bit to get the fit I wanted on my rockers.

Tue Aug 26, 2014 1:22 pm

Mcmaster Carr has 18mm shims down to .1mm thick which is about .003"...

http://www.mcmaster.com/#standard-shims/=tg9lra
click on the metric shims and then go to 18mm size.
If I was going use them to shim a set of rockers I would make sure to put the thins one between the thicker ones, and use the "Spring Steel" shims.

Casey

Tue Aug 26, 2014 4:41 pm

A thin shim should work fine sandwiched between the others shims. Would nut use one all alone tho.

Wed Aug 27, 2014 4:34 am

think how thin the endplay shims are... i wouldn't be worried if it had good oil supply?

Wed Aug 27, 2014 6:30 am

I think oil pressure is a given. Having the proper shims just makes for a quieter drive train.

Wed Aug 27, 2014 6:39 am

modok wrote: A thin shim should work fine sandwiched between the others shims. Would nut use one all alone tho.
I agree with Modok. Those .005 shims are pretty flimsy. If for some reason it started to seize and cause a wrinkle it would be all over.

Wed Aug 27, 2014 7:36 am

I have SCAT rockers and when I opened the package the sides of the rockers were not machined smooth and tore up the thin shims.
I ended up machining the sides, used thicker shims and it has not beed a problem since.
I used valve spring shims.
Some of the side play was at .060".
Using those .010" shims will be destroyed if not sandwiched between 2 thicker shims.
Just make sure the sides of the rockers are smooth.
You can smooth them by sanding them on a flat surface with emery cloth and oil in a circular motion.

Wed Aug 27, 2014 7:36 am

Deleted duplicate post.

Wed Aug 27, 2014 9:46 am

I used some of the stock shims which were .040+/-.
That combined with the packaged shims which were .032,.020 and .010 got me a little closer to what I wanted.
I measures all the shims, spacers and rockers to make the best fit possible.
So far my valve train is quieter than with the stock parts.

Thu Aug 28, 2014 12:00 pm

I always reserface the rockers&blocks and add a slight chamfer to the split on the blocks so it dosent dig into the shims.I like thick shims,but ...on occassion used thin shims between the thicker ones. I try for around .008" +-.002"side clearance. but remember the pushrods are at an angle pushing toward the rear of the car so the rear side of the rocker is the side that takes the thrust load.I try to use atleast 2 shims on the rear/thrust side of the rockers perferalby thick hard shims. and this final ajustment shims on the non thrust side. one more item...valve spring shims are not rocker shims,there made to stop roatation!!!! they are non slip shims!!!(the ones that have serations or stampings on the faces) a hardened shim is spring steel, and when bent will spring back,not stay bent.. I also remachine the rocker blocks/shaft end caps so I can use the shim pack I need for the thrust side.

Mon Sep 01, 2014 7:45 am

mark tucker wrote: one more item...valve spring shims are not rocker shims,there made to stop roatation!!!! they are non slip shims!!!(the ones that have serations or stampings on the faces) a hardened shim is spring steel, and when bent will spring back,not stay bent.

Who in their right mind would put the serrated side to the side of the other shims?

The VSI's (valve spring insert) are used on the non load side of the rockers thus allowing them to take up the clearance without causing any problems with non-rotation.

I always put the shims on my lathe to polish them using a mandrel I made to anchor them.
I find it comical how one can charge the money for a set of rockers that Scat does and expect the average Joe to install them and expect them to function properly when the sides of the rockers are so rough from casting textures.

I made a mandrel to hold the rockers too so I can polish them up on the lathe.

Mon Sep 01, 2014 8:07 am

damicotile wrote: mark tucker wrote: one more item...valve spring shims are not rocker shims,there made to stop roatation!!!! they are non slip shims!!!(the ones that have serations or stampings on the faces) a hardened shim is spring steel, and when bent will spring back,not stay bent.

Who in their right mind would put the serrated side to the side of the other shims?

The VSI's (valve spring insert) are used on the non load side of the rockers thus allowing them to take up the clearance without causing any problems with non-rotation.

I always put the shims on my lathe to polish them using a mandrel I made to anchor them.
I find it comical how one can charge the money for a set of rockers that Scat does and expect the average Joe to install them and expect them to function properly when the sides of the rockers are so rough from casting textures.

I made a mandrel to hold the rockers too so I can polish them up on the lathe. indeed who in thier right mind would market them as rocker shims.they belong under the spring.not on the rocker shaft.

Mon Sep 01, 2014 8:31 am

They aren't marketed as rocker shims but do work as rockers shims if treated right. This is why there are so many mods one has to put into place to make this aftermarket crap to work.
I rarely have a part that doesn't need to be modified to some degree to make it work or last.
To this day I have had no problems with the shims binding or being destroyed.
You just have to use them on the side with the least load.

They are checked each time the valves are adjusted by me removing them and checking for wear.
So far they work fine.

Mon Sep 01, 2014 10:33 am

I bought some rocker shaft shims from bugpack if I remember correctly and they are indeed valve spring shims. So they are marketing them as such. Needless to say they went back.

Mon Sep 01, 2014 12:12 pm

I have a HF diamond grit block with 4 different grits. When I used the very used 1.25:1 VW rockers I hand ground them flat on the sides - one side had a 1/16" protrusion that was the original unworn surface running against the stands....

I also handground regular steel washers to get the correct sideplay....

Tue Sep 02, 2014 7:58 am

just remember there not hard like a good rocker thrust shim is. although you can heetreet them a bit, be sure to go over them with 6000-8000 wet before usage.I have not used any of them.but Ive seen plenty and laughed at the bp package with them in it then threw it in the trash. scat and empi have good shims(or did last time I ordered them). a .015 HP vsi shim is just fine to use there flay with no serations. i dont recall the numbers for the 3 diferent od&id sizes.

Mon Sep 15, 2014 7:36 pm

I ordered some of these spring steel shims in .1 and .2 mm from McMaster Carr. They seem to be a good material (as in springy), the surface finish is very good and they are FLAT, no apparent punch operation. I shimmed my rockers to a loose zero with the thinner shims between the old thick shims I had in there. I must say it is so much quieter now and my old adjustment was no more than .005-.006 clearance. The Scat 1.25 rockers have a few thousandths clearance on the shaft and any extra side clearance really lets them move about. I have the Hoover mods and the Scat swivel feet rocker adjusters so I think oil flow will be fine. I think they will be just fine....