Roller rockers messed up

[chermik1999]

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?

 

[dvw]

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

 

[chermik1999]

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?

 

[threewood]

If you are worried about the valve sweep, contact B3 Racing for valve geometry rocker shaft shims.

 

[chermik1999]

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?

 

[chermik1999]

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.....

 

[Geoff 2]

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...

 

[chermik1999]

Hey brother. Long time..
So what your saying is to run it?

 

[chermik1999]

BTW..I did solve the 440 problem...lol. what a ride that was.

 

[Geoff 2]

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.

 

[dvw]

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

 

[threewood]

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.

 

[chermik1999]

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.

 

[chermik1999]

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.
View attachment 1919613View attachment 1919614

Looks pretty cool. I'll call them anyway. Thanks.

 

[chermik1999]

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.

 

[chermik1999]

Well new update.
Ran it on run stand and broke in cam. Really tight she is. Hard to start when been run for a while. I know machinist had tight PTW clearances in believe. But runs well. Took a while for lifters to pump up. Like 15 mins. Sounded like a ol mopar 5.9 diesel

 

[chermik1999]

But have some trouble shooting in store. Started tuning and vac gauge gives 10 hg which is normal for that cam. Just needle is shaky. Maybe needs more run time. Hope I didnt wear out valve guides that fast with that rocker geometry..lol
Will try off the PCV vac port on back tomorrow. Could be restricted in the front port?

 

[icetech]

I don't know what cam you have but my howards roller (.525 235@50 on 109), i get 8-10hg at idle, have run smoke through the intake to make sure i didn't have leaks just in case, it is what it is..

The 15 mins for lifter to pump up scares me though but i'm not an expert and someone else will chime in i'm sure. If you are saying it's tight and hard to start after running (due to slow turnover/tightness?) I would cut the oil filter open before i ran it again just to see if anything is in it. It's like $10 that might save you a lot more in the long run..

 

[451Mopar]

On a Mopar shaft mounted rocker system, pushrod length does not change rocker to valve tip geometry.
The reason it changes geometry on an adjustable stud type rocker is the rocker pivot point changes with pushrod length.
The Rocker stands on a Mopar fix the rocker pivot point and most people just use them as is.
This means where the rocker contacts the valve tip (without changing pedestal height) only depends on the rockers arm length and the valve stem height.

The minimum scrub theory is to have the rocker pivot point 90 degrees to the valve tip at 1/2 valve lift. This does not consider rocker arm length where the rocker contacts the valve stem tip, so different rockers might contact the valve stem tip at different points.

Here is a good article: https://www.eliminatorproducts.com/...pbHZtWUhNQjdObEJtdHdqdjZLQWlMaDVzRGRrdz0=.pdf

 

[dvw]

But have some trouble shooting in store. Started tuning and vac gauge gives 10 hg which is normal for that cam. Just needle is shaky. Maybe needs more run time. Hope I didnt wear out valve guides that fast with that rocker geometry..lol
Will try off the PCV vac port on back tomorrow. Could be restricted in the front port?

On a Mopar shaft mounted rocker system, pushrod length does not change rocker to valve tip geometry.
The reason it changes geometry on an adjustable stud type rocker is the rocker pivot point changes with pushrod length.
The Rocker stands on a Mopar fix the rocker pivot point and most people just use them as is.
This means where the rocker contacts the valve tip (without changing pedestal height) only depends on the rockers arm length and the valve stem height.

The minimum scrub theory is to have the rocker pivot point 90 degrees to the valve tip at 1/2 valve lift. This does not consider rocker arm length where the rocker contacts the valve stem tip, so different rockers might contact the valve stem tip at different points.

Here is a good article: https://www.eliminatorproducts.com/...pbHZtWUhNQjdObEJtdHdqdjZLQWlMaDVzRGRrdz0=.pdf


The Miller article is very good. The one item that can be challenged, is that his belief the the 90 degree rule is gospel. Nothing is gospel in the engine building world. The 90 degree rule does function well. And you will not get into trouble using it. What does using 85 degree, or 95 degree get you? Different cam motion at different ares in the lift curve. Is this a bad thing? None of us here are running the perfect camshaft. How many different lobes are available with the exact same durationand lift, it's mind boggling. This takes way more dyno time, testing, and money than any of us have. Could it make more/less power, for sure. In my opinion the valve guide wear theroy is BS. The lifter has way MORE side load than a valve. Are lifter bores worn out quickly with agressive lobes? I will give my example. My drag car with 330#/810# spring load, .484"/.471" lobe lift (roughly 830/.800" at the valve). Rocker geometry is .060" higher than ideal. (yes it has been measured). 13 years, 1200 runs, two touch up valve jobs. Never had a guide changed for wear. Still in spec well below .002".
Doug
Doug