#1  
Old 05-18-2023, 09:22 AM
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spectramitch spectramitch is offline
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Default Adjustable Guide Plate Issue

Aligning my roller tips to the push rods I am noticing my contact pattern is heavy on one side of the valve. The Roller tip is centered on the valve, the roller itself is tilted or "Cambered" slightly. It appears the stud when torqued is pulling into the clearance on the guide plate. With out a guide plate I get a good even patch. Has anyone had to run washers or anything under their studs on top of the guide plates to flatten the seating out? These are Pre 2002 E heads with 3/8" pushrods and Harland Sharp Rockers.
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  #2  
Old 05-18-2023, 12:12 PM
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mysticmissle mysticmissle is offline
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i see the guide plates say isky, I would say they need to be adjusted as you suspect. Are they all showing that off centered ness or just one or two? I have seen the adjustables welded in place after set up to avoid movement and ease reassembly if they are ever taken out from under the rocker studs.

I have used speed master plates on speed masters wo issue, have not compared to edelbrock. But i have a set of each i may be able to compare tomorrow morning if it helps

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Old 05-18-2023, 12:44 PM
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You might need to enlarge the rocker stud holes in the guideplates so the chamfer on the bottom of the stud won't contact the hole in the guideplate and move it in some unwanted direction.

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Old 05-18-2023, 03:16 PM
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spectramitch spectramitch is offline
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Quote:
Originally Posted by mysticmissle View Post
i see the guide plates say isky, I would say they need to be adjusted as you suspect. Are they all showing that off centered ness or just one or two? I have seen the adjustables welded in place after set up to avoid movement and ease reassembly if they are ever taken out from under the rocker studs.

I have used speed master plates on speed masters wo issue, have not compared to edelbrock. But i have a set of each i may be able to compare tomorrow morning if it helps
It's probably 50/50 some worse off than others. When I set the guide plate on a flat surface plate it will rock around a bit. I am going to get some grade 8 flat washers. Also grind the high spots down on guide plate and see if any better. Im definitely welding them now, its a real PITA to get them to stay put when tightening.

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Old 05-18-2023, 03:44 PM
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might be better off just buying the edelbrock ones maybe?
if you add washers its going to change your push rod length, may put you in a different predicament unless your pushrods have been moved and you need the adjustability?

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Last edited by mysticmissle; 05-18-2023 at 03:50 PM.
  #6  
Old 05-18-2023, 06:37 PM
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Quote:
Originally Posted by mysticmissle View Post
might be better off just buying the edelbrock ones maybe?
if you add washers its going to change your push rod length, may put you in a different predicament unless your pushrods have been moved and you need the adjustability?

Yeah no dice on the washers. They are raising the stud to high that i am actually threading poly lock into the shoulder and cannot get my lash. I am not sure if i need the adjustability. I do not have any offset lifters or rockers. I think I may get the edelbrocks. Are they cleared for 1.65 rockers already?

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Old 05-18-2023, 08:03 PM
mgarblik mgarblik is offline
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I have several sets of the Edelbrock supplied guide plates. PM me if you want them for postage + 10.00 for a set.

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Old 05-26-2023, 09:18 AM
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With the new guide plates from mgarblik, I had to make a fixture and machine them to 3/8". The fixture really made it a breeze. I did mock it up first with some 5/16 pushrods to make sure I should open them up on center. The new guide plates totally fixed my problem. Nice and flat contact patch. Thank you so much Mike I appreciate your generosity!
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Old 05-26-2023, 01:33 PM
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I tried the Iskys on my RAIV heads when I went to 3/8" pushrods and the slot was not deep enough

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  #10  
Old 05-26-2023, 06:24 PM
mgarblik mgarblik is offline
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Glad that worked out. Got to keep as many Pontiac engines on the road as possible!

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