Pushrod Guide Plates
 

I'm in the process of reassembling my engine and installed Comp Cams 4806 guide plates per the recommendation of the head Mfg - Dart. The previous set of Manleys were cut and rewelded to correct the geometry of the valve train. The Comp Cams appear to work on all but (2) valves - #3 and #2 cylinders.

Which is better, slot the mpounting hole for the play to move the guide or cut and weld the guide?

Any other ideas?

Do not know how yours are but mine would not line up other than cutting and rewelding guide plates. Slotting would not do the trick. Depends if both guides are off. Mine only needed to move one side if that makes any sense.

I had the same problem and used guide plates from GM for a 427.....that took care of it. I don't have the part number around but got it at the dealer....

??, Ive never had any problem with guide plates. Are you saying the slot did not line up the pushrod with stud and valve? Have I just been lucky?

I HAD THE SAME PROBLEM ON A SET OF DART HEADS ON 540 MERLIN TALL DECKS.I TRIED COMP PLATES AS DART RECOMENDED BUT THEY WOULDN'T CLEAR. I TRIED EVERY BRAND PLATE I COULD GET MY HANDS ON BUT THEY WOULD NOT LINE UP. I HAD TO END UP GRINDING THE HEADS FOR CLEARANCE.IF YOU GRIND THE SLOT IN THE GUIDE PLATE WIDER IT TAKES THE HARDENED FINISH OFF OF THE SURFACE AND WILL CAUSE PROBLEMS DOWN THE ROAD.

My problem was rocker arm not centered on valve stem. Nothing to do with length of pushrod.

Yea, thats what I meant. Length is a whole other issue. Ive used Merlin heads and mostly GM and never had that problem. ??

I've got Merlin heads. My engines will be out in about a week. I can see what guideplates are in there then. Like formula 31 said, I've never had any problems. Don't Merlins use stock Chevy parts and geometry?

I would have dart address this issue or have them refund so you can use a set of merlin heads,there an extremly large company and should have come across this issue prior,maybe talk with someone ther politly who has more experience or who does there R&D....relieveing the strenght at the slot is a questionable situation,then again you may have to cut and weld 6 or 8 guide plates to get on exactly were you need it,and slotting the mounting hole is a direct risk due to the fact your also moving the location of the second pushrod on the plate,dart has sent new sets of heads to us prior when finding out there were casting problems,they seem to be great people and know what your trying to acheive.....

dunno what to tell you.....thats just the way mine worked out after I reconfigured my pushrod lengths and had the new pushrods in....maybe I got a bad run of the comp cams guide plates....it would'nt be the first time they had bad runs of parts!!!! (like lifters for instance......)

hey pantera,got a buddy who runs another shop here in tampa that just came over complainin about the exact same problem w/the guide plates,I went over and checked them out and it seems they had a batch that are misdrilled,and like him,there gonna need replaced!

I have found that my Crower stainless roller rockers, if swapped from stud to stud will give a different alignment with the valve stem. I took two rockers and set them up with a cut Chevy guide plate then welded them.. Went thru both heads, when I came back to put the other rockers on, they were off..

I used Comp guide plates, several sets differnt seasons and they all seemed to be built the same, but rockers didnt line up.

I believe T&D rockers when installed address this issue, but with a rocker shaft you have to watch that the roller tip is paralell with the vavle stem.. more issues.. Wish they would perfect the solenoid valve actuators. Then use a computer to do the bump stick work..

my .02

Dick

I had an issue 2 years ago with the Comp Guide Plates on my Merlin Heads. Pushrod guide plate on number 7 broke for the exhaust valve. Thank god I didn't drop a valve. Replaced the guide with a stock GM pushrod guide, the roller and replaced the valve and I was good to go.

After that happened I spoke to the guy at my machine shop and he told me that he had a lot of problems with the aftermarket guides and swears by stock GM pushrod guides.