Just got the valve train together and noticed some of the rocker rollers are not centered above the valve stems.
I can push the same rocker side to side and get the alignment results captured in the attached pics.
I know I'll have to move the guideplates around to adjust the centering but I'm wondering if the guideplate slots are too wide for my pushrod diameter.

How much side-to-side play is acceptable?

 

pushed the other way

 

i dont have any experience with guide plates, but i dont think that's right, the guide plates should be just a hair wider then the pushrod, post pics of the pushrod/guide plate area, also have you dyno'ed that motor? i'm going to be building a 355 and have accel base/runners and was thinking of using that lpe 211 cam

 

Are you running stock push rods in 3/8" guide plates?

 

Looks like a 5/16" pushrod in a 3/8" guideplate to me.

 

Just went and checked the pushrod guides. They are fine. I'm running 5/16" pushrods but not stock. They're the expensive Comp ones.

While checking the rockers, I noticed the rockers are sliding side-to-side on the rod they ride on (full-roller rockers). There are snap rings limiting the side to side travel. Looks like I might be able to get a really thin washer beside the snap ring to act as a shim.

Anyone else have this issue with Comp Pro Mag roller rockers?
Is there an actual spec for side-to-side travel?

 

This is not uncommon. Yes you will need to loosen the rocker studs and move the guideplate around until it's centered between the intake and exhaust. I've always had one or two that don't line up properly.

 

On a couple of cyls, I have one rocker that needs to go one way and the other rocker is perfect (perfectly centered, but still sloppy). If I make one better, the other will get worse. Should I just split the difference?? I'm running ~400 lbs open spring press and I'd really like to keep the rockers squarely on top of the valve tips.

On the rocker shaft, I measured the gap between the lockring and the rocker body at .018-.020". Anyone have a pro mag rocker handy they could measure and compare gaps??

I slid a .015" feeler gauge into the gap and the side-to-side play on the rocker looked real nice over the valve tip. I'm hesitant to place a soft metal washer in there as a shim cause I'm afraid it might get chewed-up and particulate my eng with metal bits.

 

How old are those rockers? They may need to be rebuilt to remove the side to side motion. I'd call Comp Cams and ask their tech dept.

 

A couple of my rockers didn't line up like that. Common practice is to cut the guideplate, rotate it until the rocker lines up then reweld the guideplate together. I had to do that to 2 of my guideplates. Look under the rocker cover of many race cars and you'll see the same thing.

My guideplates are just wide enough for the pushrod to slide past.

 

Isky adjustable guide plates work good with no welding

 

When I first assemvled my 388 I had the exact problem. I bought another set of guid plates to cut and masacre for experimenting sake but no matter what we did it still came out a little less than perfect, alot of it had to do with the spacing of the valves and placement of the area where rocker studs screw into since heads have slightly larger runners minimal shifts in part positions are expected even though companies claim stock 23* valvetrrain parts.

I gave up and ran it with the guidplates I did'nt butcher and said wtf, give it a shot and split the difference to try and make it as happy of a medium as possible. Never had any valvtrain troubles in all the years I ran it, no valvestem problems or roller tip problems.

 

Cutting the guide plates and welding them back actually sounds like a good idea to perfect the centering. I may wind up doing just that.

The rockers only have abt 10K miles on them. I did email Comp Cams to see if what they think of shimming the rockers for side to side slop. No reply yet. Hopefully I'll hear something back from them after the holidays.

Anyone have pro mag rocker they can measure the gap on??

Thx for all the replys.

 

It helps to have a MIG welder at home since you need to weld them while on the car and in position. I just packed a bunch of wet rags around the guideplate and welded it back together once I got the rockers in the position I wanted.

You really want them to look like picture #2 but for a typical engine, picture #1 will still work fine.

 

I have a MIG welder at the house and the eng is on the stand, so no problems there.

When I tore this eng down, I noticed some of the valve tips were scarred a little. Not real bad. The machinest was able to clean them up pretty easily. At first I thought they got scarred by piston debris floating around (had a piston with a broken ring land).

I also had #8 intake valve guide severly worn (with only 10K miles on eng). Guide was replaced.

When I saw this alignment issue, I started wondering if it had something to do with the scarring and worn guide issue.

The front-to-back looked pretty good on the rockers. I was staying in the center 1/3 of the valve tip with the roller tip.

So the (mis)alignment shown in pic#1 is acceptable?
After I adjust (cut-weld) the guide plates and center-up the rockers over the valve tips, the alignment will be a little better than depicted in pic#1. That makes me feel a little better..

I'd still like to tighten up the side-to-side play seen within the rocker assys. Guess I'll have to wait on Comp Cams to reply abt that.

 

Finally got a reply from Comp Cams. They tell me the side-to-side slop in the rocker assy is normal. They don't recommend trying to shim the slop fearing I might burn up something at high RPM.
I was able to re-arrange/re-adj the guide plates and got all but 1 to work pretty well.

On the remaining cyl, the guide plate needed to be "stretched" since one pushrod need to go one way and the other pushrod needed to go the other way. I was going to cut and re-weld that plate but hated to dig out all the welding stuff just to make one weld not to mention having to pack wet rags around everything near-by.

With the aid of a large ball-peen hammer and a anvil, I was able to make one of the guide plates slightly longer (and a little thinner). The openings for the pushrods had to be dressed up afterwards since they skrunk a little in the process.

Using one of the pushrods and an unmolested guide plate I was able to get the side clearance for the pushrod (.016"), then filed the slots on the massaged guide till they matched. Everything looks pretty well centered now. On to the next phase..