Adjustable Pushrod Guideplates for a Magnum 5.9

[jmanhoff]

Hey all,

I've been chasing a ticking sound with my Magnum 5.9, and determined it to be a horrible valve job by the company who made the heads, problem is no longer an issue as I went from non-adjustable Harland Sharp rollers to stud mounted adjustable. Problem is, with the guideplates, I can't seem to get the rollers centered on the stems. Some are fine, some are not so fine. Worst one is almost a quarter of the way off the side of the stem. I'm using the Comp 4825-8 plates, and from reviews and other forums I've read that they have bad quality control where some of the pushrod slots are tight, and the rockers don't sit centered, even with adjustment which are both issues I'm having. I've looked for some adjustable guideplates but only have found some for Ford and Chevy engines. I'm not apposed to slotting the stud holes, but I'd prefer getting different adjustable style guideplates if any existed, or if I could use a Ford or Chevy style?

Of course, the Magnum heads are 5/16 thread, and the studs are 3/8 so I have a conversion stud for the rockers, but the hole itself in the guideplate needs to be for a 5/16 bolt.

 

[PRH]

Any adjustable guide plates I’ve seen have slotted bolt holes to fit 7/16” threads.

I’ve never had a set on hand for a SBF, so those might be different.

Before adjustable guide plates were a thing, on aftermarket BBC heads in particular, the roller to valve alignment was often crap.
It wasn’t unusual to cut the plates in half, adjust each 1/2 so the roller alignment was correct, then weld them back together.

 

[TT5.9mag]

It wasn’t unusual to cut the plates in half, adjust each 1/2 so the roller alignment was correct, then weld them back together.

That is exactly how I did the guide plates in my BBC.

 

[TT5.9mag]

Hey all,

I've been chasing a ticking sound with my Magnum 5.9, and determined it to be a horrible valve job by the company who made the heads, problem is no longer an issue as I went from non-adjustable Harland Sharp rollers to stud mounted adjustable. Problem is, with the guideplates, I can't seem to get the rollers centered on the stems. Some are fine, some are not so fine. Worst one is almost a quarter of the way off the side of the stem. I'm using the Comp 4825-8 plates, and from reviews and other forums I've read that they have bad quality control where some of the pushrod slots are tight, and the rockers don't sit centered, even with adjustment which are both issues I'm having. I've looked for some adjustable guideplates but only have found some for Ford and Chevy engines. I'm not apposed to slotting the stud holes, but I'd prefer getting different adjustable style guideplates if any existed, or if I could use a Ford or Chevy style?

Of course, the Magnum heads are 5/16 thread, and the studs are 3/8 so I have a conversion stud for the rockers, but the hole itself in the guideplate needs to be for a 5/16 bolt.

Bending the ears of the guide plates slightly can work if you’re not too far off.

 

[TT5.9mag]

You can also use a self aligning SBC rocker.

 

[jmanhoff]

I’ve read about the welding trick but annoyingly I don’t have easy access to a welder at the moment or I would’ve done that. I know that people file the slots for the pushrods so they actually freely move. Is that something I can do with the stud holes? Sort of slot them so I can move them where I need them? Or would that create a risk of the bolts backing out and moving over time

 

[jdsduster]

my magnum heads had slotted guild plates for adjustability

 

[PRH]

Slotted bolt holes aren’t a problem……. That’s how the adjustable plates are made.

 

[jmanhoff]

Slotted bolt holes aren’t a problem……. That’s how the adjustable plates are made.

I guess that was a dumb question. Alrighty lol, I’ll slot them and see how that goes.

 

[jmanhoff]

Okay, well. Back at it again.

I slotted the guide plates (which was fun because of how hard the steel is), and centered all the rollers.

Replaced my stock manifolds back with the JBA shorties I had before and remflex gaskets. I confirmed there is no exhaust leaks. I then got the engine hot and set the rockers while the engine was running.

Ticking is still there. It’s very interesting to me that with the non adjustable Harland rockers, the ticking was louder hot than cold. The adjustable rockers it’s the opposite. I did once again confirm that all 16 rockers have oil, and my oil pressure is solid. I got a new gauge that actually works. 70 psi cold idle, 25 warm, 50 cruise.

 

[Ceedawg]

Any adjustable guide plates I’ve seen have slotted bolt holes to fit 7/16” threads.

I’ve never had a set on hand for a SBF, so those might be different.

Before adjustable guide plates were a thing, on aftermarket BBC heads in particular, the roller to valve alignment was often crap.
It wasn’t unusual to cut the plates in half, adjust each 1/2 so the roller alignment was correct, then weld them back together.

Use Oldsmobile guides plates, sliced then welded back(too wide) use SB Ford studs and rockers. I had gotten all this then bought the Chrysler kit so these are for the next build. Buy CM SB Chevy push rods (special length). The Chrysler guide plates had nylon inserts to use the stock pushrods