Lets talk Roller Cam Lifters.
- Thread starter Cudafever
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pishta
I know I'm right....
cast and steel are about the same, billet is just the way it was shaped. Ill call no difference on the wheels.
dusterbing the peace
FABO pyrite member
Roller wheel material really only changes with higher spring pressures. Typically as the cam lobes get more aggressive the cam is machined from a billet instead of a cast core. More aggressive lobes plus the higher associated engine speeds require more spring load to control the valve train...which is how we get to the harder materials mentioned above to avoid grinding the wheel and cam into Oblivion.
You'd want to "match" materials so to speak, but price points usually take care off that. Most people probably wouldn't buy the cheap cam with the expensive lifters... unfortunately the opposite is usually true which is one thing that can contribute to lifter failure.
You'd want to "match" materials so to speak, but price points usually take care off that. Most people probably wouldn't buy the cheap cam with the expensive lifters... unfortunately the opposite is usually true which is one thing that can contribute to lifter failure.
Hemioutlaw
Make America Great Again!
A quick background;
As a machinist for over 40 years who has fabricated everything from Dies for Punch Presses out of Tool Steels (A2, D2, O1, S7 etc.) to building Transfer, Compression and Injection Molds for Plastics and Rubber (P20, H13 etc) and now building Deep Water Completion Tools for the Oil and Gas Industry that are subjected to the harshest of conditions (Inconel's and Chromes). Over the course of my career I've also machined an endless number of different materials in the Aluminum, Plastic, and Rubber family's.
Generally when they are referring to Aluminum, As a long time Racer I've Always chuckled when I see Performance Aftermarket Manufacturers touting the usage of the word "Billet" which in reality means nothing more than the product they are selling has been produced from a Solid Bar of material as opposed to a casting process. Depending on the quality of the casting there is a case to be made that a "Billet" product can be stronger than a "Cast" one due to the grain structure and a machined part can maintain closer tolerances and will have a better appearance But............. as your doing your shopping for whatever bear in mind that 'Forged" parts are going to be the Strongest!
*While I'm certainly no expert on Rocker Arm Geometry or Design I would have to imagine that irregardless of the Rocker material used that it's the quality of the Roller Bearings that plays a heavy role.
Note: "Metallurgists agree that a forged piece of aluminum is stronger than cast or billet. The reason being, when the material is shaped under pressure, its ‘grain’ follows the same shape as the part. As a result, the product manufactured is stronger due to the continuous grain characteristics allowed by the forging process."
Thanks for the education hemi
was told that billet was the strongest do too grain. Very interesting
Ok so mass is the deciding factor. get it. 1200 dollars roller on a small roller cam would cause heavier springs without any benefit.
was told that billet was the strongest do too grain. Very interesting
Ok so mass is the deciding factor. get it. 1200 dollars roller on a small roller cam would cause heavier springs without any benefit.
yellow rose
Overnight Sensation
The reason the .750 wheel is the "industry standard" is because that is the biggest wheel you can fit in an .842 body. In other words, because Chevrolet architecture is garbage, we all get garbage. That's why the .750 wheel is used.
A narrower wheel on the lobe will INCREASE the unit loading and cause MORE friction.
Your last statement is just dead wrong. It's not a balancing act of anything.
You run the biggest body with the biggest diameter wheel you can fit in there.
dusterbing the peace
FABO pyrite member
Thanks for the info, thought I knew something from reading other stuff. Deleted my post to avoid spreading bad info.
I went and tried to find the thread that it was take about in. But couldn't find it. should have asked the question them.
I think it was a Jones solid roller lifter???????
Something about that lifter would have changed the cam spec a little?????????
Hope that jobs someone memory on that? Maybe i was just dreaming.......not it was on one of these thread in the past week or so.
I tried to use the search button also and got nothing so the spelling could be way off as well.
Ok maybe it's the way the cam is ground????
I found it by the way and here is the post.
many of us were thinking of a conversion to a mech flat tappet so ignore all the lifter size stuff
what matters is what was said on my post 79 about the torque advantages of an inverse flank roller cam- no one else takes the time to final grind and spark out with a 5" wheel
several other "inverse" series are barley inverse - as much as can be obtained with the standard 18 " wheel which is not much
Mikes program takes all this into account
cheeers
Maybe a little bit more explanation on this.
I found it by the way and here is the post.
many of us were thinking of a conversion to a mech flat tappet so ignore all the lifter size stuff
what matters is what was said on my post 79 about the torque advantages of an inverse flank roller cam- no one else takes the time to final grind and spark out with a 5" wheel
several other "inverse" series are barley inverse - as much as can be obtained with the standard 18 " wheel which is not much
Mikes program takes all this into account
cheeers
Maybe a little bit more explanation on this.
Irregardless is not a word.
I don't know where that work came up in this thread, but thanks for you time.
j par
Well-hung Member
I'm not bringing a lunch today so by 2 I'm going to be hungry!!...
yellow rose
Overnight Sensation
Right...it's an inverse radius on the lobe. It works, but. AFAIK, the only cam grinder doing it correctly is Mike Jones. Others offer an inverse radius, but if you don't use some incredibly small diameter grinding wheel on the cam grinder it doesn't really work that well.
I've said before back in the mid 1980's I tried an inverse radius lobe from Crane. That thing was a spring killer.
I will say that maybe today, with better springs those lobes may have worked better. Valve spring technology has jumped up by several orders of magnitude since then.
in·verse
/ˈinvərs,inˈvərs/
Learn to pronounce
adjective
OK that's the best i can do........
so how does this.....backward? lobe? work?....look like?
And how is it an advantage????????
/ˈinvərs,inˈvərs/
Learn to pronounce
adjective
- opposite or contrary in position, direction, order, or effect.
"the well-observed inverse relationship between disability and social contact"
- something that is the opposite or reverse of something else.
"his approach is the inverse of most research"
OK that's the best i can do........
so how does this.....backward? lobe? work?....look like?
And how is it an advantage????????
yellow rose
Overnight Sensation
If you picture a cam lobe with flat flanks leading to the nose, and then imagine that same flank wit ha point on it where the flank itself would look like it has an a point where the lifter actually looses lift (IIRC the lifter literally doesn't lose lift at that point but the inverse radius basically stalls the lift rate.
That's the only way I can explain it. Rather than a flat flank, the flank has a dip in it, for lack of a better term.
As to why it is better, I'm not sure. I do know there are cases where it works. What parameters those may be I can't say.
j par
Well-hung Member
... Thank you for the cheeseburger...
yellow rose
Overnight Sensation
yellow rose
Overnight Sensation
I'm pretty sure the science behind it has merit. I suspect (guessing is more like it) that what you are doing with that lobe shape is at a certain point in the lift curve (again, I suspect the cam grinder will have an idea where this should occur) where the lifters rate of lift is slowed down considerably to get the valve to spend more time between say .200 lift on the opening side to .200 lift on the closing side.
It's probably somewhere more like .400 lift if what I'm saying makes sense. You are effectively slowing the valve opening down at certain lift points.
Again, just speculation.
Ok next question.
Why do you have to block off the lube to a mechanical roller lifter. They have to make mechanical lifter that feed oil up thru the push rod tube to feed mag/chev tip rocker arm.
So why is this tubing or sleeving required on a mechanical Roller lifter. and for that matter why is it not required for mechanical Flat Tappet lifter?
Why do you have to block off the lube to a mechanical roller lifter. They have to make mechanical lifter that feed oil up thru the push rod tube to feed mag/chev tip rocker arm.
So why is this tubing or sleeving required on a mechanical Roller lifter. and for that matter why is it not required for mechanical Flat Tappet lifter?
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Post #5. It reminded me of my friend Billy Peyton who used to say it all the time. He died last year from injuries sustained in a motorcycle accident. I would tell him the same thing when he said it and he would look at me and say "it's MY word, dammit, F you Rob" lol
TT5.9mag
Two atmospheres are better than one
A good read on YB with some intelligent people contributing.
Facts About Inverse Radius Roller Profiles
Facts About Inverse Radius Roller Profiles
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