Neither do I, but evidently PRW does. You'd think they'd at least test the theory.
Stainless, Bushed PRW Rocker Arms
- Thread starter Mopar69gts
- Start date
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Yes, you can see what you see is getting oil. Are they all? Obviously not, I don't believe.
You are correct ,
I cannot see all of them.
But remember what is on my Engine now is a old original set of 273 rockers with Factory banana grooved shafts.
I just happened to have from a boat engine someone gave me.
They showed little to no wear, I cleaned them up used them for several thousand miles when the first set of PRW Rockers wore out.
When the second set of PRW Rockers wore out recently, I dug back out the 273's checked them over they still show Zero wear.
They are back on currently and seem to be just fine.
But I do plan to pull them off and re inspect.
When I do I will post pictures and how they are holding up.
I think your right about the oiling grooves that is pretty much proven here.
PRW Rockers failed twice with no grooves.
Old original 273 rockers have not with grooves.
And they are 55 years old...
Mike
You know, I KNOW which rockers I would leave on. However, I would nanner groove them.
U also don’t have any spacers under the shafts. Kim
Actually I do.
I kept on the b3 spacers Mike made for the PRW Rockers.
They helped to get the nose of the 273 Rockers more towards the center of the valve tip.
I talked with Mike about that he said that would help for sure.
The Geometry is probably not as good as with The PRW Rockers, but better then with No spacers.
Rat Bastid
Dunamis Metron
Check the 273 shaft diameter and measure the bores of the PRW rockers. If you have .002-.003 clearance run the 273 shafts.
I don’t get why anyone thinks this is anything but an oiling issue. The bronze bushing is grabby. It need MORE OIL.
Groove the shafts or use your 273 shafts. The 273 rockers are grabbing the shafts because they are ductile IRON, UNBUSHED. If you bushed them and didn’t use a groove and VERIFY your clearance they’d grab the shaft too.
YOU DO NOT HAVE ENOUGH OIL AT THE SHAFT FOR BUSHED ROCKERS.
I'm going to send them to Gary at RAU.
He said he would check them over for me free of charge.
If he thinks they are worth fixing I might go that route.
He said for $ 380
He would re bush them and chrome the shafts, I don't remember if he was going to add oiling grooves or not.
But he did say he thought that was the problem (no grooves. )
So he was probably going to add them.
That was before finding about half of the roller tips are wearing flat.
So they may just not be cost effective.
But if nothing else I'd like to hear his Professional opinion after he sees them.
He also talked with me about making a set of bushed 273 Rockers with a 1.6 ratio.
I'll keep you guys posted.
Thanks
JDMopar
Well-Known Member
Next time you pull them off to have a look see, take a look at the bottom side of the shaft, and particularly at the bolt hole in the shaft where the oil comes up from the cam thru the head to oil the rockers, and see if that hole is larger than the other hold down bolt holes in the shaft. I dug out some old factory rocker arm shafts today to see if there was a difference in that hole size, and there was. 2nd hold down bolt hole from the end when you bolt them down correctly. Hold the shaft with the end that has the notch in your left hand and look at the 2nd bolt hole in to see if it is bigger. Interestingly, I looked at a set of rocker arm shafts that came off of a set of 302 heads, and the 2nd bolt hole from each end is bigger to let oil get into the shafts and feed the rockers. Those 302 shafts have no notches in them, and can't be put on wrong like the older ones. Check that on your 273 rocker shafts and also the aftermarket ones that keep screwing up on you. I bet the 273 shafts have the bigger hole to let the oil into the shaft and the other ones may not.
Thank you for that,
And yes the oil holes in the factory 273 shafts are larger then the others.
They are installed correctly , Notch down facing inward.
Or like you said looking at whichever side of the engine your putting them on, notch down to your left.
I'll check the PRW Shafts
I believe that all the holes are the larger size incase someone wants to use 3/8" hold down hardware.
But I'll need to verify that.
The PRW Shafts have oil holes on top and bottom so you can't install wrong.
The first set only had oil holes on the bottom
The second set is drilled straight through.
Thank you
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Mike,
I believe you must have misunderstood me, and I don't want others to get the wrong idea.
The Trick Flow heads have the rocker stands repositioned for to have geometry more suited for a roller rocker. It can't be right for every application, but it is much closer than other heads on the market that copy the stock head. The 273 rockers, or any non-roller rocker for that matter, are not recommended for the Trick flow head. The reason it looks better with the spacer is because the 273 rocker is too short for that stand position. When the shaft is raised, and it is already too high for that rocker, it may center the pattern, but at full lift it stands the rocker up on its nose and scrubs the valve tip excessively. Over time it will wear out the guides, just like a stand position that is too low can do. It will pound the seats out of the head prematurely, as well, from the high valve closing velocity.
I've heard reports that Trick Flows tech line has said that stock rockers can be used on their heads. That is contradictory to the information included with the cylinder heads which states roller rockers are required.
Give me a call when you have some free time. I may have a helpful option for you in the near future.
As far as the reports you've heard,
Trick Flow did tell me 273 Rockers
Would be a good choice.
That was the original plan.
Then after researching on this site
I quickly learned you were the go to guy for this.
I'm glad I did.
Thanks again Mike
We have been doing this mod for several years and for several engines. We have no oiling issues ever since. This is only needed to be done when using studs.
One other thing is the lifter bores. If the bores are worn and the lifters are loose in the bores you will lose oil pressure . at that point pushrod oiling won't do a dam thing. My son watches some of the builders on this site and said its a dam shame some of you believe their bullshit. The engines that leave this shop never have any oiling issues. Part of blueprinting an engine is making sure all the machining is accurate.
After some of the idiots condemned my suggestion on oiling tips that we used that work very well I thought I would see where this thread went. And just like I thought some of the best suggestions are dammed by many that don't have a clue.
No oil flow? Parts wear real fast. 6 years of racing the indy headed 340 and no wear at all
Thank you for that,
Do you have a couple studs ready to go?
And are they the same length as the Trick Flow head takes?
I know this isn't a sale thread.
If you want to pm me that's fine too.
Thanks
You need to index the studs your using . Meaning, Put them in where they will be, Tighten them up and mark the stud at the feed hole so when installed they line up with with the groove cut in the stud. Install yours , Mark them , And then send them to me or take them to a local machine shop. The groove is cut in the stud with a ball mill. We won't charge you anything to face 2 studs. Just the shipping. SK Machine, Danielsville Pa.
Will do,
That's Great thank you!
mopar head
Well-Known Member
Dumb question, why just studs and not bolts?
The studs are almost the same diameter as the hole in the head. The bolts are tapered so the oil flow is not restricted.
Rat Bastid
Dunamis Metron
Because the bolts are necked down. I’ve been running studs for almost 40 years and never had an issue.
Take a stud and slip it into any newer aluminum head and see how tight they are. Also you can never be sure the stud is in the center of the hole to leave the oil feed hole side open. The taper on the bolts center the bolt for oil feed. The studs are straight cut and have no taper in the shank to center them.
I too never did this and been doing theses engines since the 70's. After building several high dollar engines and taking my engine to HTA machine (Very knowledgeable engine builder) My son and I learned some tricks on many different engines. There are many other tricks we learned from him. Like side bolt mains he installed. RB's use 3/8 bolts and B engines use 5/16 studs. Unlike many know it alls on this site we learn and use methods that make sense. Sometime you have to think with your "dipstick" Jimmy
Bakerlite
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Well I pointed out issues with your lifter bore wear statement, and you had no response for that.
So who's the bullshitter?
Rmoore
Well-Known Member
Thanks for the info and the visual aides !
Post #1 ----- pic#1 ---- bushing material looks like brass. Not a good choice for a bushing. Compare it to the bushing in a full floating connecting rod, which has a similar movement, but with much more force on it.
----- pic#4 very different looking shaft surfaces even though they are side by side. Oil works when its in the right places.
----- pic#4 very different looking shaft surfaces even though they are side by side. Oil works when its in the right places.
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