Yeah my small block PRW rockers have 2 bushes per arm & the rocker shafts only have one set of oiling holes at the bottom. Mine also have the oil feed to the roller/valve tip side at the top of the arm instead of underneath like the ones pictured here.
Stainless, Bushed PRW Rocker Arms
- Thread starter Mopar69gts
- Start date
-
Yeah my small block PRW rockers have 2 bushes per arm & the rocker shafts only have one set of oiling holes at the bottom. Mine also have the oil feed to the roller/valve tip side at the top of the arm instead of underneath like the ones pictured here.
Rat Bastid
Dunamis Metron
You MUST have a groove on the shaft with hydraulic lifters. With a hydraulic lifter there is never any clearance between the rocker and the shaft. The groove gets oil between the rocker and the shaft.
Really the shaft should have a groove no matter what.
When you see the bushing leaving materiel on the shaft it’s because there isn’t any oil there.
I’m not a fan of using pushrod oiling and Chrysler oiling together. The OE oiling system will works.
Really the shaft should have a groove no matter what.
When you see the bushing leaving materiel on the shaft it’s because there isn’t any oil there.
I’m not a fan of using pushrod oiling and Chrysler oiling together. The OE oiling system will works.
put a small grove in #2/4 cam journals all the way around journal about .035 wide and .015 deep this is how you keep shafts alive .a lot of extended road racers and stock cars with hydraulic cams rules .
Mike at B3 Racing Engines is a cool guy. Bought a Hydraulic roller cam, geometry kit, Morel 5321 lifters and PRW 1.6 rockers for my 340". Even though I still have the factory shaft oiling that uses a solid pushrod, after reading that he recommended oil through pushrods I think I'll do that. Wonder if a stock replacement M72 will be fine or if i need the M72HV if I use oil through pushrods. May not matter.
I would talk with Mike before adding pushrod oiling.
He did suggest that to me because of the Bushing wear on mine.
And I have a HV oil pump.
But if your not having any excessive Rocker arm/ shaft wear then I don't think He would recommend pushrod oiling.
You're right Mike is a Cool guy!
He really cares about helping you get the most out of your combination.
Gotcha... I have a M72 and an M72HV to put in my engine when the builder gets going on it just not sure If id need HV for a 99% street driven car with a stock oil pan.
I drove up to PA from NC to let Mike measure my heads to make his geometry kit. Talked for about 90 minute then I headed home. He knows his sh*t for sure.
I drove up to PA from NC to let Mike measure my heads to make his geometry kit. Talked for about 90 minute then I headed home. He knows his sh*t for sure.
Rat Bastid
Dunamis Metron
If you are running hydraulic lifters you MUST have grooved shafts. It’s not an option.
What proof do you have that grooved shafts are reqd? For any style of lifter.
[1] The rockers have grooves already in the bronze bushes for lubrication.
[2] There was oil getting to the rockers, you can see oil pooling from the shafts in post #1.
[3] There is oil clearance for the rockers; if there wasn't, the rockers would be tight/jammed on the shaft.
[4] I'll bet there are many people on this site using adjustable rockers without grooved shafts & having zero wear problems.
[5] The OP provided two separate oil paths for rocker lubrication & the bushes still wore. Because of poor quality bronze.
[6] If grooved shafts were reqd [ for warranty ] , wouldn't a warning note be included with the rockers??
[1] The rockers have grooves already in the bronze bushes for lubrication.
[2] There was oil getting to the rockers, you can see oil pooling from the shafts in post #1.
[3] There is oil clearance for the rockers; if there wasn't, the rockers would be tight/jammed on the shaft.
[4] I'll bet there are many people on this site using adjustable rockers without grooved shafts & having zero wear problems.
[5] The OP provided two separate oil paths for rocker lubrication & the bushes still wore. Because of poor quality bronze.
[6] If grooved shafts were reqd [ for warranty ] , wouldn't a warning note be included with the rockers??
Bakerlite
Well-Known Member
- Joined
- Nov 12, 2007
- Messages
- 6,431
- Reaction score
- 3,311
You have to be very careful if you do this.
Bakerlite
Well-Known Member
- Joined
- Nov 12, 2007
- Messages
- 6,431
- Reaction score
- 3,311
For me, pushrod oiling ensures that the top of the pushrod, where it meets the rocker adjuster gets a good supply of cooling oil. Especially big rollers used on the street. That's the main reason I use it.
In this country, I've pulled down Chrysler engines that had pushrod oiling from the factory.
Why is the roller tip worn if the rocker is getting adequate oil ?
Remember the roller skips rather than roll.
Bakerlite
Well-Known Member
- Joined
- Nov 12, 2007
- Messages
- 6,431
- Reaction score
- 3,311
Well I've used both designs over the years, I've come to my conclusions through trial and error.
Plus, the grooved shafts were a factory item.. right?
Last edited:
Fishmen,
Now you are changing the story. In post #28, you said the roller 'skids'. In post #62 you say it 'skips'. Want to have another try, LOL.
Skid & skip are two different things.
A roller that is round [ not oval or out of shape ] & has the axle hole accurately drilled in the centre, rolls across the valve tip.
If the roller has flat spot, there could be a few reasons. Binds on the axle, high spot on roller or out of round, axle hole drilled off centre, poor quality/soft steel.
Now you are changing the story. In post #28, you said the roller 'skids'. In post #62 you say it 'skips'. Want to have another try, LOL.
Skid & skip are two different things.
A roller that is round [ not oval or out of shape ] & has the axle hole accurately drilled in the centre, rolls across the valve tip.
If the roller has flat spot
skid, skips whatever it still doesn't roll
mopar head
Well-Known Member
Be neat to have clear valve covers and paint mark a roller to see how much they roll or not.
It's already been done by Racer Brown. lol and someone else I know.
mopar head
Well-Known Member
My mid 90s Lincoln welder has ohv adjustable SL rockers that are shaped like a curved shoe. Pretty neat design which I think would do well in an automotive application too.
????
Post #65.
The roller doesn't roll. Then the rollers would flat-spot. Last time I check, none of the rollers in my roller rockers had flat spots, been in over 20 yrs & driven weekly.
Hands up anybody who has flat spots on the rollers of their roller tip rockers.......
The roller doesn't roll. Then the rollers would flat-spot. Last time I check, none of the rollers in my roller rockers had flat spots, been in over 20 yrs & driven weekly.
Hands up anybody who has flat spots on the rollers of their roller tip rockers.......
M/head,
If the curved shoe you are describing is what I think it is, then it has been in use for decades. Stamped factory rocker arms. Some good descriptions of cam follower design in Don Hubbard's Camshaft book.
If the curved shoe you are describing is what I think it is, then it has been in use for decades. Stamped factory rocker arms. Some good descriptions of cam follower design in Don Hubbard's Camshaft book.
mopowers
Well-Known Member
If roller tips don't roll, what's the point? Wouldn't a solid pin do the same thing if that was the case? Not trying to start (or even contribute to) an argument. I just don't understand the point of a roller tip if it doesn't "roll" on the valve stem.
mopar head
Well-Known Member
Your probably right, it probably wore so much and shaped the tip like a shoe. With the hours on the machine, I was told it had the equivalent of 300,000 miles on a car.
IIRC that tip is replaceable. Yes the old boy is done, blow by, needs rebuilt. Still runs/works! , but I retired it.
B3 Racing geometry part 2 explains it.
Rat Bastid
Dunamis Metron
The PROOF is every single performance rocker shaft is grooved so you can get some oil between the rocker and shaft.
With a hydraulic lifter there is always a upward load on the rocker. Always. So you expect 30, maybe r0 pounds oil oil pressure to lift the rocker off the shaft? It won’t because at the shafts you probably have less than 10 psi.
Ever look at the difference between a cam that’s had a solid lifter on verses a hydraulic lifter? If you had, you notice a clear wear mark all the way around lobe including the base circle. You don’t see that with a solid because of LASH.
gzig5
Well-Known Member
May not have anything to do with it but when I got my PRW 1.6 rockers I stripped them down and ran them through the ultrasonic tank. Then I still had to clear every oil port hole with a wire. I’d say 30% of them were packed with chips or crud. I cleaned the shafts out as well as I could without removing the plugs but I may go back and do that again because I haven’t installed them yet. If yours weren’t cleaned out before they were put in you could have restricted oil flow on some. Either way with any of these parts it’s important to pull them down and clean them out because manufacturers are taking every shortcut that they can to save a buck.
I also don’t like the color of those bushings and the deposit on the shaft it almost looks like there’s too much copper or wasn’t blended well so it could be an issue with the material
I also don’t like the color of those bushings and the deposit on the shaft it almost looks like there’s too much copper or wasn’t blended well so it could be an issue with the material
-
