OEM Rocker Arm Side Play

[12many]

The fundamental differences are quite obvious to you, myself and many others no doubt, some may not understand, but it is clear to all the amount of side to side play I have shown in this case is excessive, as I and a few others have already mentioned. As I’ve basically said, in the case of the stamped rockers, most would likely bolt on and roll. I’m just glad I can get the spacers in the width we need easily without having to resort to making them to yield the side clearance and that the rocker tips will also be pretty much centered over the valves.

Something I find interesting is in the Mopar Performance engine book there are references made to rocker arm-to-valve tip relationship for both hydraulic and mechanical assemblies (obviously both oem versions) and how to rectify by using a hyd. or mech. specific MP spacer kit to move the rockers up or down the shaft to align them, including grinding the rocker itself to move towards the pedestal. No mention that I can find about side to side clearances.

 

[Ironracer]

whatever happened to that? kinda lost track of it.

Rusty told me I was going crazy... I'm not sure I can quote him, verbatim, but it went somewhat like " Stop the Madness!." And the server crashed after... I still don't remember that sound. I put that thing together around 2012... I don't know what to think..

 

[PRH]

It would appear the text in the manual and the parts in the catalog don’t agree with each other.

Edit- After reading that a few times....... I think it’s just semantics.
A poor choice of words.....”up and down” the shaft....... is really “left or right” on the shaft.

 

[12many]

It would appear the text in the manual and the parts in the catalog don’t agree with each other.

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Edit- After reading that a few times....... I think it’s just semantics.
A poor choice of words.....”up and down” the shaft....... is really “left or right” on the shaft.

I wonder what the thickness of the “production style” spacers is. I’ve been searching for specs but all I see is they are out of production and no results from the more well known vendor searches.

 

[PRH]

no idea, but stock BB spacers are basically .200” thick

 

[PRH]

I have almost no SB stuff in my shop, but I do have a 596 head and some stock rocker gear off a 318.
Bolting those crusty old rockers on the 596 head ended up with the pairs having barely .035” between them.
Rockers are 1.665”-ish wide.
Hold down clamps were basically 1.245” and .945”.

The other end of the spectrum I’ve seen are the Mancini/HS BB rockers and hold downs on Ede heads.
Bolt it all on and they’re jammed up solid.
Slightly less than “0” clearance.

 

[pishta]

I bought a set of those spacers from MP through PAW but never put them on a stamped rocker setup. In 35 years of Mopars, I never ran a stamped rocker....On a hydro, there is constant pressure on the rocker from the pushrod (preload) and its not 100% perpendicular to the rocker shaft so they are always being pushed in one direction to wherever position that is stopping them. I dont think an idling motor will show any side to side movement of a stamped rocker in any application, just rockers that have found their operating position and do their job.

 

[PRH]

Just to be clear, the .015” shims Mopar was selling are listed for “adjustable” rockers....... not the stamped hyd rockers.

 

[33IMP]

First, I know next to nothing about Mopar small blocks. But I know the big block holddown brakets look very similar... but they have small "rubbing pads" (for want of a better description) on each end of the holddown. I have had to grind the pads down, and sometimes completely away, to get adjustable rockers centered up on the valve, then use spacers inbetween to maintain location.
I wondering if those smallblock hold downs have been ground on? I sure would use some sort of shim to locate those rockers better than the video shows.

 

[PRH]

The SB hold downs don’t have the “tabs”.

I listed the widths of the old untouched ones that I test fit earlier.

 

[12many]

I have almost no SB stuff in my shop, but I do have a 596 head and some stock rocker gear off a 318.
Bolting those crusty old rockers on the 596 head ended up with the pairs having barely .035” between them.
Rockers are 1.665”-ish wide.
Hold down clamps were basically 1.245” and .945”.

The other end of the spectrum I’ve seen are the Mancini/HS BB rockers and hold downs on Ede heads.
Bolt it all on and they’re jammed up solid.
Slightly less than “0” clearance.

I’ve got original rockers and hold downs off of the 78 360 and the rockers are about 1.662” wide, hold downs are .961” & 1.259”

Have hold downs off an 87 318 which measure .958” & 1.257”

On the big blocks they use spacers, small blocks no. Anyone have the definitive reason (or even a theory?) why that is?

 

[12many]

These replacement Melling rockers measure about 1.652” and the originals off the 78 measure 1.662” Per pair thats .020” extra clearance using the Mellings, so the clearance with all the original 78 pieces would have been about .140” (vs. .160” w/Mellings) Still excessive. Ok? Apparently so. Like it? Nope

 

[mopowers]

Would it be bad to toss in some .125" spacers? I believe 440source carries them.

 

[PRH]

Got an old stock head kicking around to test fit that stuff on for grins??

 

[12many]

Would it be bad to toss in some .125" spacers? I believe 440source carries them.

I mentioned in an earlier post I am planning on running some Harlands, they have some .125” spacers, albeit in aluminum. I’d prefer steel, was wondering what size the MP ones were.

 

[12many]

Got an old stock head kicking around to test fit that stuff on for grins??

No, all aluminums now.

 

[PRH]

Might want to verify with HS, but I’m pretty sure the .125” spacers are steel.

I think all the spacers they sell for the Mopar rockers are steel.

 

[12many]

Might want to verify with HS, but I’m pretty sure the .125” spacers are steel.

I think all the spacers they sell for the Mopar rockers are steel.

Only reason I mention being aluminum is Mancini lists them as such.

Harland Sharp Rocker Arm Shaft Spacers

 

[PRH]

Summit shows the same thing for the .062” shims.
Must be they’re made out of magnetic aluminum.

 

[12many]

Summit shows the same thing for the .062” shims.
Must be they’re made out of magnetic aluminum.

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Never believe anything you read!!

 

[Ironracer]

Never believe anything you read!!

Damn Shame, ain't it?

 

[12many]

I’ll be calling Mancini tomorrow to hopefully order in stock parts and find out what they are made of

 

[mopowers]

Here's another option if the mancini spacers aren't what you're looking for:

Rocker Shaft .125" Spacers (Set of 16) - New-440 Source

 

[PRH]

I like the price of those from 440source

 

[12many]

Good lord it never ends with these USA made Melling rocker arms! Out of the sixteen, five of them have issues with how they fit on the rocker shaft. Inconsistent stamping for valve spring clearance and pushrod causes them to contact the shaft as indicated in pictures below. Some relieving must be done so that the bottoms of the rockers actually contact the shaft.
After initial measuring for pushrods there was too wide a variance vs. within a reasonable range. Closer inspection reveals the reason(s) Some rockers riding lower on the shafts than others which is easily rectified, AND the Speedmaster valve heights being all over the place! Added up and we got a mess.

If anyone thinks they can buy these heads, and use new hydraulic oem style rocker arms and a set of identical pushrods and all will be good, beware. You might luck out but.....
The required lengths between the pushrods on our setup vary up to .100”. IMO, best bet is using adjustable rocker arms to accommodate the valve heights.
Time to ponder our next steps