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Discussion Starter #1
Below I used my stock length 3/8" (8.280 ?) 'intake-pushrod' on a exhaust valve.
How's this for a wear pattern? My guess it's a tad too short ?
It favors the intake side of the valve tip but not by much.
ALSO... what will it do when I add 1/4-1/2" turn preload for the hyd roller, move even further towards the intake side?
I'll make a adjustable pushrod for thei ntake side by cutting a old 3/8 PR and threading in some all-thread.


 

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being narrow is more important then being perfectly centered IMO
.050 width/pattern from a full cycle is sweet and i would run that length PR
Lots of peeps dont realize how important valve train geometry is how much power you leave on the table when it is not right:)devil
Hyd rollers are a PIA when checking witness marks cause the internal plunger is collapsing giving you a false reading
I have heard of guys making the HYD lifter solid (temporary)
you should be ussing a wimpy "checking spring" with the adjustable checking PR
 

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being narrow is more important then being perfectly centered IMO
.050 width/pattern from a full cycle is sweet and i would run that length PR
Lots of peeps dont realize how important valve train geometry is how much power you leave on the table when it is not right:)devil
Hyd rollers are a PIA when checking witness marks cause the internal plunger is collapsing giving you a false reading
I have heard of guys making the HYD lifter solid (temporary)
you should be ussing a wimpy "checking spring" with the adjustable checking PR
How would you make a hyd lifter temporarily solid??? Im having the same problem with my lifters... Even with a very lite checking spring it still plunges into the body. I thaught about getting a lifter from summit and just welding it in place making it solid for checking this...

Im open to ideas....
 

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steelcomp was here
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Hammer,
Have you read any of the threads on checking for push rod length?
Your rocker needs to be at 90* to the valve stem at mid lift. Period. It doesn't matter where the tip of the rocker sits on the valve (within reason)
You have to take into consideration the amount of lifter preload (add that to the length of your pushrod) when figuring.
Use as stiff a spring as your checking pushrod will allow. There's more deflection than you'll imagine. If possible, run the entire valve train while checking. If you just use "checking" springs, you will end up with pushrods shorter than necessary and the rocker will be under-arced. To what degree will differ from engine to engine. Could be as much as .030" -.040" on heavy roller springs.
For checkiong hyd. rollers, you can use a solid roller and note the difference in length between it and the hyd you're going to run, and figure that into your P/R length. The critical different is from the OD of the roller to the P/R seat cup (the distance from the cam to the P/R), not the overall length of the lifter body.
 

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steelcomp was here
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Thanks for your reply Steel...
90 degrees of which plain???

OR
The shape of the body of the rocker makes no difference. What's important it that the plane through the center of the two rotational points of the rocker (in the case of a roller, it's the trunion and the roller tip) is at 90* to the valve stem at mid lift.
Here's a pic:



This plane:

 

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Discussion Starter #6
The shape of the body of the rocker makes no difference. What's important it that the plane through the center of the two rotational points of the rocker (in the case of a roller, it's the trunion and the roller tip) is at 90* to the valve stem at mid lift.
Here's a pic:

Ohhhhh center of the trunion and roller > I knew that :)sphss
Shucks Steal, I'm gonna need a damn good eye to eyeball 90* off the rocker to valve stem with my combo square :))eek:)) :D
 

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This plane:

Steel.... when you are 90* at mid lift, the pattern is also the smallest on the top of the valve from what I understand :)bulb may not be center:mad: but has the smallest sweep:)bulb

Is this true???

Steel your right it is a pain in the A$$
 

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steelcomp was here
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Steel.... when you are 90* at mid lift, the pattern is also the smallest on the top of the valve from what I understand :)bulb may not be center:mad: but has the smallest sweep:)bulb

Is this true???

Steel your right it is a pain in the A$$
Yes, this is true, and seldom is it centered.
PITA, yes...but IMO an important one.
 

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Discussion Starter #10
Ok, so here's what I did.
1)install a dial indicator on top the valve retainer.
2)zeroed it out on the heal of the cam
3)rotated the needle 6 times for .600 lift (needle rest at O)
4)backed off 3 turns = .300
5) you can't see it but there is a black marker center of the trunion and roller >>> and it looks pretty darn close to 90* to the valve stem.
Ohhh, and I used my good eye too!:)sphss

 

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steelcomp was here
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Ok, so here's what I did.
1)install a dial indicator on top the valve retainer.
2)zeroed it out on the heal of the cam
3)rotated the needle 6 times for .600 lift (needle rest at O)
4)backed off 3 turns = .300
5) you can't see it but there is a black marker center of the trunion and roller >>> and it looks pretty darn close to 90* to the valve stem.
Ohhh, and I used my good eye too!:)sphss

It "looks" close, but some how put something up there that's 90* and make sure. Cut a piece of cardboard, use a small square, a piece of plastic, something to verify. You're going to all this trouble, take the last step. YOu can use the machining marks on the trunion and roller axle as perfect centers. It doesn't take much to make a difference, but that does look pretty darn close.
 

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Hammer, if it helps, get yourself some key stock that you can lay across the top of the retainer. The closer the thickness of the key is to reaching the center of the nose roller the better. If needed, you can use feeler gauges under the key to make up the difference. Make sure the key is long enough to extend over to the trunnion. You can use anything that sets flat on the retainer and is tall enuff to reach the center of the nose roller. This the place to guess. It needs to be dead nutz or don't bother.



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Discussion Starter #14
Hammer, if it helps, get yourself some key stock that you can lay across the top of the retainer. The closer the thickness of the key is to reaching the center of the nose roller the better. If needed, you can use feeler gauges under the key to make up the difference. Make sure the key is long enough to extend over to the trunnion. You can use anything that sets flat on the retainer and is tall enuff to reach the center of the nose roller. This the place to guess. It needs to be dead nutz or don't bother.
Very good suggestion and it works excellent!
I put two white pin head paint marks on the center of the trunion & roller. When the retainer/bar stock is paralle with the two dots that's 90* to the valve stem.
I also used my small slide square as Steal did off the two dots...also on the money.
My junk is "dead nuts on". :))THumbsUp

Hopefully after work tomorrow I'll make it to the machine shop in time to measure up and order the proper length p-rods
 

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I have always done the pattern check and I'm getting ready to try Steelcomps 90 degree at mid lift method
and I have one question, Does the rocker adjustment setting affect the pushrod length?
How much do I adjust the rocker to start with?
 

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hammer did you check all 16 rockers, i know it's a pain in the a$$ but depending on the machinist was smoking that day you may find something out of wack,nows the time to find out and fix it.
 

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steelcomp was here
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I have always done the pattern check and I'm getting ready to try Steelcomps 90 degree at mid lift method
and I have one question, Does the rocker adjustment setting affect the pushrod length?
How much do I adjust the rocker to start with?
Not really "my" method, just "the" method, and I preach it like the gospel. ;) The rocker will be where it will be when the pushrod is right. As you adjust your adjustable pushrod, the rocker will move up or down on the stud accordingly...you have to remember to re-check your lash every time you re-adjust your adjustable pushrod. It's a trial and error method...you just keep working it untill it's right.
 

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steelcomp was here
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Very good suggestion and it works excellent!
I put two white pin head paint marks on the center of the trunion & roller. When the retainer/bar stock is paralle with the two dots that's 90* to the valve stem.
I also used my small slide square as Steal did off the two dots...also on the money.
My junk is dead...so are my nuts :))THumbsUp

Hopefully after work tomorrow I'll make it to the machine shop in time to measure up and order the proper length p-rods
:)hand
 

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Not really "my" method, just "the" method, and I preach it like the gospel. ;) The rocker will be where it will be when the pushrod is right. As you adjust your adjustable pushrod, the rocker will move up or down on the stud accordingly...you have to remember to re-check your lash every time you re-adjust your adjustable pushrod. It's a trial and error method...you just keep working it untill it's right.
Thanks Scott, If I ever get my head bolt problem figured out I can start on this.:|err
 
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