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Roller rockers messed up

chermik1999

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Hey guys. A new one for me at least.
Doing a LA360 for my son. I started out with a set of Speedmaster heads and matching suggested Proform roller 1.5 rockers from Summit.
Well we know how the heads went. Found 2 non seating Ex valves and no support as it was a year to the day I did the install. Anyway such as it is.
Got a new set of peformance world heads Sent. I have had good luck over the years.

Anyway installing these rockers which are for SB. But what the heck? I messed up the first set of push rods length from Smith bros, so re measured and got a new set Sent.

Now these darn things dont work at all? Doesn't matter how I line em up without a push rod, they are just off. Im afraid to buy another brand now if these are poorly made.

1st set of heads albeit Speedmaster fit better and now these ones are worse. Maybe should just got to stamped to get this engine finally started? Unless im doing something wrong?
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Are you are taking about the pattern on the valve being towards the exhaust side? If so either the rocker is too long (likely) or the pedestal where the shaft is mounted isn’t spot on for the lift at the valve. or are you talking pushrod clearance in the head That may need clearancing which is pretty normal. With a low lift .550” os so I’m not so worried about where the valve tip pattern lies. Perfect. No. Usable. Yes.
Doug
 
Well everything else is good. Just was worried about the off center pattern and when at lift a bit worse. Does it ride off the edge? No. But im worried about abnormal valve stem wear.
Q. Why would this happen? PW has heads that match the rest with exception of speedmaster. But even they fit more center? Bad manufacturing of the Proform cheap rockers? They're like .100 short?
 
If you are worried about the valve sweep, contact B3 Racing for valve geometry rocker shaft shims.
 
Hum...thats a good idea. Didn't know they have em.
But it would appear that I need like a .100 lift to get them centered. Not sure that's doable?
 
Are you are taking about the pattern on the valve being towards the exhaust side? If so either the rocker is too long (likely) or the pedestal where the shaft is mounted isn’t spot on for the lift at the valve. or are you talking pushrod clearance in the head That may need clearancing which is pretty normal. With a low lift .550” os so I’m not so worried about where the valve tip pattern lies. Perfect. No. Usable. Yes.
Doug
Ya Doug. Out towards the exhaust. But lift isn't crazy. I have to check, but maybe .488?
Only way to get more centered is a shorter rocker or big shim.....
 
Abnormal [ valve guide ] wear. Hmm. That happens when you go for the centered mark across the valve stem tip that everybody raves about........because at max lift, the roller is NOT centered & is pushing on the SIDE of the valve tip.....& at max lift that is where the SIDE thrust on the guide is at it's maximum....because.......that is where is spring tension is at it's maximum.

A centered mark on the valve tip is meaningless & unless you know hat it does to the pushrod side [ longer or shorter needed? ]. Look at the change in lift these different prod lengths caused...

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BTW..I did solve the 440 problem...lol. what a ride that was.
 
What I am saying:
The action of the rocker is quite complex. There is the valve side....& the prod side. The position of both will determine the final overall ratio & will likely be a compromise.

D. Vizard tested various rockers & took measurements. A real eye opener.

img368.jpg
 
We can all read up on valvetrain geometry theory. That being said, Mopar heads have a fixed rocker shaft location. They also should have a fixed distance between the center of the valve stem and the shaft centerline for a given valve lift. The pushrod length only changes how far the adjuster is screwed in or out. The valve tip end is a fixed point. Does every motor run the same lift? No. So now there’s a compromise. Aftermarket rocker lengths vary all over the place. How smart are the designers? My small block runs a hyd roller .547”/.570”. It has Crane 1.6 Rockers. When I built it 22years ago the roller tip was off towards the outside. Crane told me the pushrod length was wrong. Told them the head was setting on the bench with the rocker shaft and rockers bolted to it. He told me it he head was wrong, um. It is a factory production head. Obviously he knew nothing about shaft rockers. Can you modify stuff to make it fit the specific valvetrain theory you want to believe in? Yes. On most applications for street hot rod stuff and milder race stuff will you see a change? No. Think about this logically. A normal aftermarket head 440 11/32” valve stem diameter is .344” with a stock length of 5.44”. How much side load is a roller wheel going to impart if it’s .060”, .080” off center? It would be like trying to push a 6 ft 2x4 sideways with you hand not centered in the middle of the end of the board. The bottom line is this stuff has been incorrect and run successfully for over 50 years. If you pulled valve covers this weekend at the big Norwalk Mopar event I would bet over 95% of them have bolt on aftermarket valvetrain that is not spot on. Do I know how to correct this issue and make it spot on? Yes. Is my racecar with 1200 passes running .830” lift with 330#/825# spring load perfect? No. The shaft is up .070” higher than it should be so it could reuse my $600 pushrods that I already had. Never had a valvetrain issue in 13 years of 7100 rpm runs.
Doug
 
Last edited:
B3R kit on my Stealth heads, Hughes 1.5 ratio rocker arms, .57" valve lift. You can center it up pretty well. Peace of mind? Yes.
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We can all read up on valvetrain geometry theory. That being said, Mopar heads have a fixed rocker shaft location. They also should have a fixed distance between the center of the valve stem and the shaft centerline for a given valve lift. The pushrod length only changes how far the adjuster is screwed in or out. The valve tip end is a fixed point. Does every motor run the same lift? No. So now there’s a compromise. Aftermarket rocker lengths vary all over the place. How smart are the designers? My small block runs a hyd roller .547”/.570”. It has Crane 1.6 Rockers. When I built it 22years ago the roller tip was off towards the outside. Crane told me the pushrod length was wrong. Told them the head was setting on the bench with the rocker shaft and rockers bolted to it. He told me it he head was wrong, um. It is a factory production head. Obviously he knew nothing about shaft rockers. Can you modify stuff to make it fit the specific valvetrain theory you want to believe in? Yes. On most applications for street hot rod stuff and milder race stuff will you see a change? No. Think about this logically. A normal aftermarket head 440 11/32” valve stem diameter is .344” with a stock length of 5.44”. How much side load is a roller wheel going to impart if it’s .060”, .080” off center? It would be like trying to push a 6 ft 2x4 sideways with you hand not centered in the middle of the end of the board. The bottom line is this stuff has been incorrect and run successfully for over 50 years. If you pulled valve covers this weekend at the big Norwalk Mopar event I would bet over 95% of them have bolt on aftermarket valvetrain that is not spot on. Do I know how to correct this issue and make it spot on? Yes. Is my racecar with 1200 passes running .830” lift with 330#/825# spring load perfect? No. The shaft is up .070” higher than it should be so it could reuse my $600 pushrods that I already had. Never had a valvetrain issue in 13 years of 7100 rpm runs.
Doug
Thanks Doug. Appreciate the feedback. You're right as how much time and $$ do i want to spend when its going to be driven maybe 10x a year. Great comment.
 
What I am saying:
The action of the rocker is quite complex. There is the valve side....& the prod side. The position of both will determine the final overall ratio & will likely be a compromise.

D. Vizard tested various rockers & took measurements. A real eye opener.

View attachment 1919501
Yup..I.get it. I'll dive in a bit more over the weekend. Thanks.
 
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