Hey everyone,

I'm in the middle of putting together a '74 455 build and could use some advice from the collective wisdom here. My goal is to run roller rockers, but I really want to keep the stock look and have them fit under my factory steel valve covers.

I know clearance can get tight with roller setups on these heads, so I wanted to see what brands/models you guys have successfully run without hitting the baffles or top of the covers (even if it requires using extra thick gaskets).

Here is the breakdown of the top-end and internal parts I'm working with:

• Camshaft: COMP Cams XR262HR Hydraulic Roller Kit (CL42-413-11)
  
• Heads: Speedmaster Aluminum Heads PCE281 2170
  
• Pistons: Speed-Pro Forged Coated Pistons (L2323F)
  
• Intake: Edelbrock Performer Aluminum Intake (standard, not the Air-Gap)
  

Has anyone done a similar setup with the Speedmaster heads and stock covers? I'd love to hear which rockers worked for you, or if there's a specific brand (like Harland Sharp, COMP, etc.) that offers a lower profile body that clears easily.

Appreciate any insights or tips you can throw my way!

 

Which rockers are you looking to use? Full rollers or roller tips?

 

Either.
But would prefer full roller

 

I have roller tips under regular valve covers using short MrGasket poly locks and thicker Fel Pro rubber gaskets.

 

I know there are valve cover spacers made of aluminum in 3/8” 1/2” and 3/4” so I would think you could use any roller rockers you wish.

https://www.google.com/search?q=olds...koIEAIYASABKAE

 

Yeah but if you space them out to far won't the valve covers run into the power brake booster?

 

My suggestions:

Use the Cometic Valve Cover Gaskets . They are 0.188 thick.
Measure your existing rocker studs. Get the shortest rocker studs that will work with your application. I used ARP 135-7101 1.75 stud height (Have a shank portion under the hex to locate guide plate)
Get the shortest poly lock you can that the top (hex portion) of the poly lock won't interfere with the top of the rocker. I used COMP Cams 4600-16 1.00 height.

Valve cover spacers may also get you into clearance issues with stock AC and alternator brackets.

 

Harland sharp shaft mounted rockers with short polylocks works and rubber with steel reinforcement gasket works. No mods

 

Speedmaster makes a shaft rocker setup for that head. But you might still have to trim the baffles in order to get them to work.

 

I used Harland Sharps but had to remove the baffles from the valve covers. Fortunately, I put in the vents from both valve covers (PCV pulls from the valley), which cuts the vent velocity enough that I didn't have any oil carryover problem at full throttle.

 

I didn’t realize HS made an Olds shaft system with a 7/16 stud/bolt. Good to know.

 

I can't find this on HS's website. Does someone have a link?

 

I have the H S rollers with stock valve covers and spacers. They fit under the Brake booster no problem. Best of all, it still looks stock.

 

Someone inferred that there was a shaft rocker system from Harland Sharp for these that bolts to a 7/16 studded head. I’ve never seen it either, that’s why I questioned it.

 

Any problems with the AC or alternator or power steering brackets

 

no, lots of room

 

Aw man would LOVE to find a shaft mount roller system that would work under the stock valve covers

I think Ill start with the harland sharps with short poly locks and see what i got

 

Besides the custom T&D Machine products setups, I only know of two "semi" shaft mount roller rocker setups.

• The Speedmaster Oldsmobile 330 350 400 425 455 1.6 Ratio Aluminum Shaft Mount Rocker Arm Set - 7/16" bolt
• The old purple Mondello 7200 roller rockers (believe they were built by HS) - 5/16" bolt

Is anyone aware of any other Oldsmobile full or paired shaft setups?

 

Are there any short poly locks I can use with these to make em fit under the stock valve covers?

 

I’m running stock valve covers on my edelbrock heads with Harlan sharp rockers. I’m using the 3/8 aluminum spacers, they work great.

 

Ate these valve cover spacers? Or something else

 

I sent you a PM. Give me a call

 

Mark, looking back I can see how my message could have been interpreted as a reference to a shaft rocker system. That was not my intent.

I installed stud mount Harland Sharps with short adjustment nuts. These fit under valve covers with baffles removed, with standard gaskets. About 1/8 inch internal clearance remained.

Sorry for the confusion.

 

Here's a set of older Mondello HS shaft mounted rollers that fit with no mods under a factory valve cover. HS still sells rockers like these but they are not purple.

 

Yes, these are Harland Sharp S50026A - 1.6:1, 5/16" bolt, $625 and would not work on the Speedmaster or Edelbrock heads with the 7/16" rocker stud.

 

I use the ARP shorty studs and the Crower short poly locks.

https://www.summitracing.com/parts/cro-86050s-16

 

3/8 valve cover spacers.

 

I live near Jesel, and even applied for a job there. They make a shaft style rocker set up, even for BBO. Pro aluminum series. Not sure if this is what you're looking for, or if it will work well in a street car. The do fit Edelbrock heads.
https://static1.squarespace.com/stat...ft+Rockers.pdf

 

You do realize these are probably the better part of 2k right?
Not sure why you would post this.

 

I was wondering about this setup, Has anyone heard of it?

 

Its basically the same concept as the Harland Sharp 50026A's. For stock pedestal rocker set ups only.

 

-Anything wrong with these (other than the price) for a moderate street build?

Doc.

 

Just the limitations of the bolt: "This rocker system is capable of handling 350lbs. of open pressure before the 5/16 bolt will fail."
So, depends on what valve springs your using.

 

Actually I use these up to the better part of 400 open. Randy Becker jr at HS says guys are doing more than that with these. I’ve done a half dozen or so like that, no issues.

 

The strain on a pedestal type rocker fastener is not the same as that of a stud type. This has been debated to death in the small block Ford world. An engineer wrote an extremely long and detailed explanation of it years ago. You can probably still find it on Corral.net or Stangnet. He debunked the ole "your gonna snap that 5/16 bolt" crap and then some. Its a tensile vs shear issue.
I use the Harland Sharp S50026As on everything that is still pedestal that I have, or have built. Hell, I even still have an unopened set of Steeda 1.72's made by Yella Terra from the nineties.

 

Heh. I've recently been collecting together some of my various stashes of Olds parts, in preparation for the aforementioned mild 350 build, and found no less than four of these rocker stand bolts:



Not sure what these came out of, I've been collecting together my widely-scattered parts to see what I have. Noticed those as I was cleaning them, tossed 'em along with some worn trunnions, rockers and pushrods.

Doc.

 

If you want to run the HS 50026 rockers, you can bottom tap the heads and use 2" long CamCar allen bolts. They are 180,000 psi and the extra threads in the head help keep them from ripping out the threads in the head. I would torque to 22 ft lb with ARP lube. McMaster has the bolts, which they list at 170,000 psi because CamCars bigger than 1/2" thread are only 170, but the smaller bolts are 180s according to the CamCar/Stanley tech paper. The HS rockers come with 1-3/4" long allen bolts in grade 8 (150,000 psi) which use the same amount of threads in the heads as the stock rockers do.

 

BTW Randy told me that in the LS world which uses M8 x 1.25 bolts (which have .315" nominal diameter vs. .312" for 5/16") the failure was the bolt ripping the threads out of the head, not the bolt breaking. I don't know what bolts he supplies with those rockers, but grade 12.9 are common with socket heads (allens) in metric. That corresponds to 170,000 psi.

 

This is a great idea.

 

they rip out of LS heads because they are threaded directly into the aluminum, no heli coil insert is used on stock LS heads