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Valvetrain geometry......mid lift pushrod measurement

Posted By: 68-scatpack-rt

Valvetrain geometry......mid lift pushrod measurement - 01/26/15 03:49 AM

Hello all.
Wondering how you guys are setting up your valvetrain geometry.

Is anyone here using the mid lift method or are you guys just trying to get a centered scrub on the valve stem regardless of how wide the scrub is?

Thoughts?
Posted By: AndyF

Re: Valvetrain geometry......mid lift pushrod measurement - 01/26/15 04:28 AM

Depends on how serious the engine is and how much money/time you want to spend on it.

For a typical street/strip SB or BB you just have to live with what you get. If you buy a good set of rocker arms then you'll be okay for .550 to .600 type lift.

If you're going to run more than .700 lift then you'll need to spend some time sorting it out. Once you get past .800 lift you'll probably need to switch to Jesel or T&D to get anything that will work.

For really high spring pressure you'll want to use the 2/3 lift rule rather than mid-lift. The 2/3 lift rule minimizes the amount of travel under load but the total scrub pattern is wider than the mid-lift method.
Posted By: B3RE

Re: Valvetrain geometry......mid lift pushrod measurement - 01/26/15 08:01 PM

Quote:

Depends on how serious the engine is and how much money/time you want to spend on it.

For a typical street/strip SB or BB you just have to live with what you get. If you buy a good set of rocker arms then you'll be okay for .550 to .600 type lift.

If you're going to run more than .700 lift then you'll need to spend some time sorting it out. Once you get past .800 lift you'll probably need to switch to Jesel or T&D to get anything that will work.

For really high spring pressure you'll want to use the 2/3 lift rule rather than mid-lift. The 2/3 lift rule minimizes the amount of travel under load but the total scrub pattern is wider than the mid-lift method.


No, you do not have to live with what you get!!! Total nonsense. Rocker geometry has to do with way more than just the rocker arm, and any roller rocker that will fit the head can have correct geometry.
Posted By: 68-scatpack-rt

Re: Valvetrain geometry......mid lift pushrod measurement - 01/26/15 11:46 PM

Quote:

Quote:

Depends on how serious the engine is and how much money/time you want to spend on it.

For a typical street/strip SB or BB you just have to live with what you get. If you buy a good set of rocker arms then you'll be okay for .550 to .600 type lift.

If you're going to run more than .700 lift then you'll need to spend some time sorting it out. Once you get past .800 lift you'll probably need to switch to Jesel or T&D to get anything that will work.

For really high spring pressure you'll want to use the 2/3 lift rule rather than mid-lift. The 2/3 lift rule minimizes the amount of travel under load but the total scrub pattern is wider than the mid-lift method.


No, you do not have to live with what you get!!! Total nonsense. Rocker geometry has to do with way more than just the rocker arm, and any roller rocker that will fit the head can have correct geometry.



Are you correcting geometry with longer or shorter valves? Lash caps? Shaft shims?
Can you elaborate on your setup methods and the desired result you are after?

Thanks,
Rob
Posted By: Stanton

Re: Valvetrain geometry......mid lift pushrod measurement - 01/27/15 12:17 AM

Quote:

No, you do not have to live with what you get!!! Total nonsense. Rocker geometry has to do with way more than just the rocker arm, and any roller rocker that will fit the head can have correct geometry.



Holy crap, here we go ... !!!!

Posted By: MR_P_BODY

Re: Valvetrain geometry......mid lift pushrod measurement - 01/27/15 12:41 AM

Quote:

Quote:

Quote:

Depends on how serious the engine is and how much money/time you want to spend on it.

For a typical street/strip SB or BB you just have to live with what you get. If you buy a good set of rocker arms then you'll be okay for .550 to .600 type lift.

If you're going to run more than .700 lift then you'll need to spend some time sorting it out. Once you get past .800 lift you'll probably need to switch to Jesel or T&D to get anything that will work.

For really high spring pressure you'll want to use the 2/3 lift rule rather than mid-lift. The 2/3 lift rule minimizes the amount of travel under load but the total scrub pattern is wider than the mid-lift method.


No, you do not have to live with what you get!!! Total nonsense. Rocker geometry has to do with way more than just the rocker arm, and any roller rocker that will fit the head can have correct geometry.



Are you correcting geometry with longer or shorter valves? Lash caps? Shaft shims?
Can you elaborate on your setup methods and the desired result you are after?

Thanks,
Rob



He doesnt like to say due to that he is trying to
run a business correcting the geometry for people...
he dont like to share
Posted By: rickraw

Re: Valvetrain geometry......mid lift pushrod measurement - 01/27/15 12:59 AM

U shouldn't talk to Andy like that
Posted By: B3RE

Re: Valvetrain geometry......mid lift pushrod measurement - 01/27/15 01:47 AM

Quote:



Are you correcting geometry with longer or shorter valves? Lash caps? Shaft shims?
Can you elaborate on your setup methods and the desired result you are after?

Thanks,
Rob



I correct the geometry by moving the fulcrum centerline to the proper location. Up, down, sideways, wherever it needs to be for a specific motor. I go for the rocker geometry points to be perpendicular to the valve at 1/2 lift with a roller rocker.
Posted By: B3RE

Re: Valvetrain geometry......mid lift pushrod measurement - 01/27/15 01:55 AM

Quote:

Quote:

No, you do not have to live with what you get!!! Total nonsense. Rocker geometry has to do with way more than just the rocker arm, and any roller rocker that will fit the head can have correct geometry.



Holy crap, here we go ... !!!!




Stanton,
I believe I talked to you at Carlisle two years ago about this subject, and if I recall, several times you returned an I answered your questions. You got it then, even when one gentleman argued with me until he stomped off in a huff. I can explain the principles behind the way I do things, but some others never explain why they give advice other than they read it in a book somewhere.
Posted By: B3RE

Re: Valvetrain geometry......mid lift pushrod measurement - 01/27/15 02:14 AM

Quote:



He doesnt like to say due to that he is trying to
run a business correcting the geometry for people...
he dont like to share




I don't mind sharing with people who don't mind hearing. I guess every time Andy says "in my book" he isn't really trying to sell it, even though he doesn't outright tell you what's in the book. Come to think of it, I'm tired of hearing stuff like "it doesn't look to bad for a Mopar", as if Mopar guys are second class car guys who don't deserve better. Or, how about this one, "serious racers step to Jesel or T&D rockers". I guess the guy who can only afford Cranes isn't really serious about winning when he rolls through the gate every weekend. After all, he is bracket racing. I've never met a dedicated racer yet who wasn't serious. Oh, and by the way, education is costly, so you'll have to forgive me if I don't give every last detail of what I know away for nothing when it cost me dearly and I worked my backside off for it. Call your favorite NASCAR shop and ask how they turn 9500 rpm for hours on a superspeedway, and see what they tell you. And you have the nerve to say I don't want to share. At least I stepped up and offered and alternative to "it's not too bad for a Mopar". I guess that's not being helpful.
Posted By: B3RE

Re: Valvetrain geometry......mid lift pushrod measurement - 01/27/15 02:16 AM

Quote:

U shouldn't talk to Andy like that



Ummm, Why?
Posted By: Anonymous

Re: Valvetrain geometry......mid lift pushrod measurement - 01/27/15 02:19 AM

Had a 440 this week--.005 off the decks, new uncut Indys, 1009 gasket, Comp 829 lifters etc Harland Sharp rockers, Manley valves--well...it took lash caps on top of the valves to get it close enough--the mix of parts, the stack up of tolorences etc ya just never know--Shaft mounted Mopar stuff is a PIA for these reasons--If you get it decent close it will be AOK--we have bred in a mess with the smorgasboard of parts we now use--shim the shaft, have lash caps on hand and go on with it. Indys Hemi heads have the two clamps on the shaft top and bottom allowing flat shims to correct--great idea that should be incorporated in all after market Mopar heads IMO
Man! I complimented Indy--what was I thinking!!!!!!
Posted By: 68-scatpack-rt

Re: Valvetrain geometry......mid lift pushrod measurement - 01/27/15 02:20 AM

Quote:

Quote:



Are you correcting geometry with longer or shorter valves? Lash caps? Shaft shims?
Can you elaborate on your setup methods and the desired result you are after?

Thanks,
Rob



I correct the geometry by moving the fulcrum centerline to the proper location. Up, down, sideways, wherever it needs to be for a specific motor. I go for the rocker geometry points to be perpendicular to the valve at 1/2 lift with a roller rocker.



Thanks for the reply.
That's my understanding of properly setup geometry as well. Some guys still shoot for a centered scrub and call it good. I was just wondering, with the shaft mount rockers, what methods were employed to move the fulcrum in relation to the tip of the valve stem.

I can see shimming the shaft up or machining the recess down but, moving the fulcrum laterally closer or furthur away from the valve stem has me puzzled.

It's my understanding that the distance from the trunion centerline to the roller axle centerline varies with rocker arm manufacturers. Is that a true statement for the mopar aftermarket rocker arms?

Trying to learn as much as humanly possible as I'll be setting up a valvetrain on my 440 later this year and I'm a detail nerd.

Thanks again,
Rob
Posted By: B3RE

Re: Valvetrain geometry......mid lift pushrod measurement - 01/27/15 02:28 AM

Quote:

Quote:

Quote:



Are you correcting geometry with longer or shorter valves? Lash caps? Shaft shims?
Can you elaborate on your setup methods and the desired result you are after?

Thanks,
Rob



I correct the geometry by moving the fulcrum centerline to the proper location. Up, down, sideways, wherever it needs to be for a specific motor. I go for the rocker geometry points to be perpendicular to the valve at 1/2 lift with a roller rocker.



Thanks for the reply.
That's my understanding of properly setup geometry as well. Some guys still shoot for a centered scrub and call it good. I was just wondering, with the shaft mount rockers, what methods were employed to move the fulcrum in relation to the tip of the valve stem.

I can see shimming the shaft up or machining the recess down but, moving the fulcrum laterally closer or furthur away from the valve stem has me puzzled.

It's my understanding that the distance from the trunion centerline to the roller axle centerline varies with rocker arm manufacturers. Is that a true statement for the mopar aftermarket rocker arms?

Trying to learn as much as humanly possible as I'll be setting up a valvetrain on my 440 later this year and I'm a detail nerd.

Thanks again,
Rob


No problem Rob,
Whenever the shafts are raised, or lowered for that matter, the rocker c-line and the valve c-line get closer or further apart, so the shafts need to be offset to maintain the proper distance to keep the roller on the tip of the valve, preferably at the center. With the differences in rocker lengths, as you mentioned, some need to be offset more than others. I show some pics on my website, and it won't cost you a dime. How's that for sharing?
Posted By: B3RE

Re: Valvetrain geometry......mid lift pushrod measurement - 01/27/15 02:35 AM

Quote:

Had a 440 this week--.005 off the decks, new uncut Indys, 1009 gasket, Comp 829 lifters etc Harland Sharp rockers, Manley valves--well...it took lash caps on top of the valves to get it close enough--the mix of parts, the stack up of tolorences etc ya just never know--Shaft mounted Mopar stuff is a PIA for these reasons--If you get it decent close it will be AOK--we have bred in a mess with the smorgasboard of parts we now use--shim the shaft, have lash caps on hand and go on with it. Indys Hemi heads have the two clamps on the shaft top and bottom allowing flat shims to correct--great idea that should be incorporated in all after market Mopar heads IMO
Man! I complimented Indy--what was I thinking!!!!!!


I hate to tell ya, but the Harlands are too long, which is why you needed the lash caps to center the roller, but you should have actually raised the rocker and offset it to center the roller. I'll bet you have a lot of sweep across the tip.
Barton uses a setup like that for the Hemi's, but the stands have to be on the same angle as the valve to use a flat shim, which Barton's is. Oh yea, WHAT were you thinking?
Posted By: 68-scatpack-rt

Re: Valvetrain geometry......mid lift pushrod measurement - 01/27/15 02:44 AM

That's a great tech article mike!

Crazy how guys will obsess over can specs and then flush it away with wacky valvetrain setup.
Posted By: B3RE

Re: Valvetrain geometry......mid lift pushrod measurement - 01/27/15 02:53 AM

Quote:

That's a great tech article mike!

Crazy how guys will obsess over can specs and then flush it away with wacky valvetrain setup.


Thanks Rob, and Amen to that brother! I've been making that point for a long time. I'm actually writing the next article right now, so hopefully my web guy and I can have it up within the next week. It is way deeper than the last one.
Posted By: Stanton

Re: Valvetrain geometry......mid lift pushrod measurement - 01/27/15 05:48 AM

Quote:

Quote:

Quote:

No, you do not have to live with what you get!!! Total nonsense. Rocker geometry has to do with way more than just the rocker arm, and any roller rocker that will fit the head can have correct geometry.



Holy crap, here we go ... !!!!




Stanton,
I believe I talked to you at Carlisle two years ago about this subject, and if I recall, several times you returned an I answered your questions. You got it then, even when one gentleman argued with me until he stomped off in a huff. I can explain the principles behind the way I do things, but some others never explain why they give advice other than they read it in a book somewhere.




Yes, you're correct. But you know that this opens a whole can of worms!

And to address Mr P Body's point about this gentleman trying to run a business and not liking to share, let's not forget that AndyF rarely misses an opportunity to promote and peddle his wares! Will Andy give you his timing cover CNC program? The answer is a simple NO. So why should this gentleman disclose his secrets. He tells you "how" he achieves near perfect geometry, the math is his proprietary information. Just like Andy's CNC program, if you want it - go figure it out for yourself.
Posted By: Anonymous

Re: Valvetrain geometry......mid lift pushrod measurement - 01/27/15 02:15 PM

Quote:

Quote:

Had a 440 this week--.005 off the decks, new uncut Indys, 1009 gasket, Comp 829 lifters etc Harland Sharp rockers, Manley valves--well...it took lash caps on top of the valves to get it close enough--the mix of parts, the stack up of tolorences etc ya just never know--Shaft mounted Mopar stuff is a PIA for these reasons--If you get it decent close it will be AOK--we have bred in a mess with the smorgasboard of parts we now use--shim the shaft, have lash caps on hand and go on with it. Indys Hemi heads have the two clamps on the shaft top and bottom allowing flat shims to correct--great idea that should be incorporated in all after market Mopar heads IMO
Man! I complimented Indy--what was I thinking!!!!!!


I hate to tell ya, but the Harlands are too long, which is why you needed the lash caps to center the roller, but you should have actually raised the rocker and offset it to center the roller. I'll bet you have a lot of sweep across the tip.
Barton uses a setup like that for the Hemi's, but the stands have to be on the same angle as the valve to use a flat shim, which Barton's is. Oh yea, WHAT were you thinking?



Yep BIG sweep but ....it was a ton better and lots of Mops run Harlands and live so WTH--I am not in a position to re-engineer all of the parts for these things--nor do I want to--I bet he will race well with it and win some races--will it be less than correct SURE it will--could I have done more --not without spending more of his $$$ for marginal gain so out the door she goes--
It is what it is--I made the best of it.
Posted By: Bigfury

Re: Valvetrain geometry......mid lift pushrod measurement - 01/27/15 07:59 PM

B3, you must remember that you can lead a horse to water in the middle of the desert. But it does not mean he will be smart enough to take a drink !! Understanding a little of what you are doing there obviously is more to be gained than just a bit of performance. Like MAYBE some durability in the long run. Have a great day. It is what it is because you allowed yourself to think that.
Posted By: B3RE

Re: Valvetrain geometry......mid lift pushrod measurement - 01/27/15 09:16 PM

Quote:

B3, you must remember that you can lead a horse to water in the middle of the desert. But it does not mean he will be smart enough to take a drink !! Understanding a little of what you are doing there obviously is more to be gained than just a bit of performance. Like MAYBE some durability in the long run. Have a great day. It is what it is because you allowed yourself to think that.


Mabe the horse isn't thirsty yet. You know, most people don't buy a burglar alarm until they get robbed.
Posted By: onig

Re: Valvetrain geometry......mid lift pushrod measurement - 01/27/15 09:39 PM

Correct geometry is important as we all know.
Some people don't know to check it, some will check it and live with it, others will put different rocker arms on and just go with it.
Mind you not on a mopar shaft system, but on a stud mounted rocker system, I had to go through 3 different makes to find one that gave good geometry. For the same engine, different makes and models had different lengths. What really ticked me off was when I called Comp cams and asked for a distance from roller tip to fulcrum, they asked why I wanted it. They gave me a hard time. I finally pushed them to get me a spec on the ultra gold which I had in my hand. They did, but they used a pair of calipers to give me the spec, and were off by .090" from my measurement, how is that for accuracy. When I called Harland Sharp, no problem, looked it up, two seconds later,gave me an exact spec. I bought the HS, not the best looking rocker, but it worked out great.

The geometry at least should be checked, then you can decide what to do, if you think spending the money is worth it or not. Interesting pics on B3RE's website, stuff is all over the place.
Posted By: B3RE

Re: Valvetrain geometry......mid lift pushrod measurement - 01/27/15 09:44 PM

Quote:

Quote:

Quote:

Quote:

No, you do not have to live with what you get!!! Total nonsense. Rocker geometry has to do with way more than just the rocker arm, and any roller rocker that will fit the head can have correct geometry.



Holy crap, here we go ... !!!!




Stanton,
I believe I talked to you at Carlisle two years ago about this subject, and if I recall, several times you returned an I answered your questions. You got it then, even when one gentleman argued with me until he stomped off in a huff. I can explain the principles behind the way I do things, but some others never explain why they give advice other than they read it in a book somewhere.




Yes, you're correct. But you know that this opens a whole can of worms!

And to address Mr P Body's point about this gentleman trying to run a business and not liking to share, let's not forget that AndyF rarely misses an opportunity to promote and peddle his wares! Will Andy give you his timing cover CNC program? The answer is a simple NO. So why should this gentleman disclose his secrets. He tells you "how" he achieves near perfect geometry, the math is his proprietary information. Just like Andy's CNC program, if you want it - go figure it out for yourself.


Well said, but I do want to mention one thing. Some of the math formulas are mine, and others I learned from some very intelligent people. I'm not going to take credit that is not due me.
Posted By: onig

Re: Valvetrain geometry......mid lift pushrod measurement - 01/27/15 09:51 PM

B3RE, take the credit.
We all learn in different forms. Listening, reading, applying, experience, seeing, experimenting ...
You are applying what you learned or were taught.
I give you credit.
Posted By: 9secondsatellite

Re: Valvetrain geometry......mid lift pushrod measurement - 01/28/15 12:20 AM

B3RE. I for one am very greatful for your insight on this matter. any time you can get the geometry correct is well worth the benefit. very little lost motion and makes it so the cam and valve action are at maximum potential. there are many VERY intelligent members on this site. some are better than others at some things but they are just as insightful. i have a great deal of appreciation for the info. i have to admit that i am still trying to get a grasp on this subject but i am slowly getting it.
Posted By: MR_P_BODY

Re: Valvetrain geometry......mid lift pushrod measurement - 01/28/15 12:31 AM

Quote:

Quote:

Quote:

Quote:

No, you do not have to live with what you get!!! Total nonsense. Rocker geometry has to do with way more than just the rocker arm, and any roller rocker that will fit the head can have correct geometry.



Holy crap, here we go ... !!!!




Stanton,
I believe I talked to you at Carlisle two years ago about this subject, and if I recall, several times you returned an I answered your questions. You got it then, even when one gentleman argued with me until he stomped off in a huff. I can explain the principles behind the way I do things, but some others never explain why they give advice other than they read it in a book somewhere.




Yes, you're correct. But you know that this opens a whole can of worms!

And to address Mr P Body's point about this gentleman trying to run a business and not liking to share, let's not forget that AndyF rarely misses an opportunity to promote and peddle his wares! Will Andy give you his timing cover CNC program? The answer is a simple NO. So why should this gentleman disclose his secrets. He tells you "how" he achieves near perfect geometry, the math is his proprietary information. Just like Andy's CNC program, if you want it - go figure it out for yourself.



This is why I posted that... he is trying to run a
business... he isnt into the sharing thing due to
the business.. thats his choice
Posted By: B3RE

Re: Valvetrain geometry......mid lift pushrod measurement - 01/28/15 01:11 AM

Thanks Onig,
I can say this, I put a lot of effort into it, so I will take credit for that.
Posted By: B3RE

Re: Valvetrain geometry......mid lift pushrod measurement - 01/28/15 01:15 AM

Quote:

B3RE. I for one am very greatful for your insight on this matter. any time you can get the geometry correct is well worth the benefit. very little lost motion and makes it so the cam and valve action are at maximum potential. there are many VERY intelligent members on this site. some are better than others at some things but they are just as insightful. i have a great deal of appreciation for the info. i have to admit that i am still trying to get a grasp on this subject but i am slowly getting it.


Thank you, and I am always willing to answer questions if there is anything you don't understand.
Posted By: B3RE

Re: Valvetrain geometry......mid lift pushrod measurement - 01/28/15 01:27 AM

[quote

Yes, you're correct. But you know that this opens a whole can of worms!

And to address Mr P Body's point about this gentleman trying to run a business and not liking to share, let's not forget that AndyF rarely misses an opportunity to promote and peddle his wares! Will Andy give you his timing cover CNC program? The answer is a simple NO. So why should this gentleman disclose his secrets. He tells you "how" he achieves near perfect geometry, the math is his proprietary information. Just like Andy's CNC program, if you want it - go figure it out for yourself.



This is why I posted that... he is trying to run a
business... he isnt into the sharing thing due to
the business.. thats his choice



I don't know, Mike. It sounded like there was more to it than that but it's ok. I will help anyone as much as I can, but I won't go bankrupt to do it. I have a family to take care of and bills to pay just like everyone else. It's not like I'm making a killing correcting geometry either. If you consider the price, and the time it takes to make a custom kit or do custom machining, I would make more money honing blocks all day. I just can't stand when stuff isn't right and it destroys parts. What I don't get is how someone will spend 10 large to build a stroker motor, and then balk at less than $200 to get the valvetrain right. But hey, that is their choice.
Posted By: dvw

Re: Valvetrain geometry......mid lift pushrod measurement - 01/28/15 02:00 AM

It's like everything else. Will wrong geometry run, in most cases yes. In that vein will a motor run with single angle valve job and out of round cylinder bores, sure. The closer to perfect everything is, the better the motor will run. How far off can various specs be? That is the million dollar question. I've run motors both ways, sloppy and worn or as good as I can make it. It all comes down to how much time and money do you want to spend? Some items are worth a lot, some a little. To some it only matters that it stays together and runs. I say learn what is correct, make a decision if you feel that is important and go with it.
Doug
Posted By: 9secondsatellite

Re: Valvetrain geometry......mid lift pushrod measurement - 01/28/15 02:05 AM

B3RE you have a pm.
Posted By: B3RE

Re: Valvetrain geometry......mid lift pushrod measurement - 01/28/15 04:33 AM

Quote:

It's like everything else. Will wrong geometry run, in most cases yes. In that vein will a motor run with single angle valve job and out of round cylinder bores, sure. The closer to perfect everything is, the better the motor will run. How far off can various specs be? That is the million dollar question. I've run motors both ways, sloppy and worn or as good as I can make it. It all comes down to how much time and money do you want to spend? Some items are worth a lot, some a little. To some it only matters that it stays together and runs. I say learn what is correct, make a decision if you feel that is important and go with it.
Doug


Oh, I've beat on some worn out junk before, Doug. That's why i referred to an expensive stroker to make my point.
Short story: I once put a very high miles junkyard 400 core in my car to run the rest of the season when I cracked a cylinder in the good stroker motor and didn't have a spare. I tore the motor down, honed the worn out cylinders, bought some .030" over 440 rings off Ebay and file fit them, and put it all back together with the lower mileage left over parts from the stroker motor and a cheap set of gaskets. I put some better heads on it and beat it until the used bearings started to rattle. Darn thing clogged my brand new radiator with rusty junk that was in the water jackets.
My point is, I had two hundred dollars in the motor, so I wasn't concerned about destroying high dollar parts. If that had been my good motor, I would certainly have been concerned. I don't think too many people are running that kind of junk, but maybe I'm wrong about that.
Posted By: CTD5.9

Re: Valvetrain geometry......mid lift pushrod measurement - 01/28/15 05:48 PM

Quote:

Oh, I've beat on some worn out junk before, Doug. That's why i referred to an expensive stroker to make my point.
Short story: I once put a very high miles junkyard 400 core in my car to run the rest of the season when I cracked a cylinder in the good stroker motor and didn't have a spare. I tore the motor down, honed the worn out cylinders, bought some .030" over 440 rings off Ebay and file fit them, and put it all back together with the lower mileage left over parts from the stroker motor and a cheap set of gaskets. I put some better heads on it and beat it until the used bearings started to rattle. Darn thing clogged my brand new radiator with rusty junk that was in the water jackets.
My point is, I had two hundred dollars in the motor, so I wasn't concerned about destroying high dollar parts. If that had been my good motor, I would certainly have been concerned. I don't think too many people are running that kind of junk, but maybe I'm wrong about that.



I'm pretty sure you just described the engine in my mud bogging truck perfectly, I don't know whether I should be depressed or relieved that I'm not the only one who has done this.
Posted By: B3RE

Re: Valvetrain geometry......mid lift pushrod measurement - 01/28/15 06:15 PM

Don't be depressed. We all do what our wallets, abilities, and time allow us to do.
Posted By: Thumperdart

Re: Valvetrain geometry......mid lift pushrod measurement - 01/28/15 06:39 PM

Quote:

Don't be depressed. We all do what our wallets, abilities, and time allow us to do.



So true................having a fast car is easy w/enuff $$$$$ and that`s why my Dart rots these dayz in the garage w/a few test runs and that`s it BUT that`s about 2 change. It`s definately a challenge to go fast on basic parts but also a welcoming challenge and after talking to Jason Pettis my new goal is to freshon my stock block w/a new 3.90 stroker kit, same rpm`s w/a valve job, but a different ring pack and bushed lifter bores and see how fast a streetable 470 can run in a 3000+ lb. car. I will be trying out the B3RE kit here soon and will report my findings. It`s our job as humans to help each other out when we can so I support the members here first when I can...........
Posted By: tsanchez

Re: Valvetrain geometry......mid lift pushrod measurement - 01/29/15 02:04 AM

Quote:

Quote:

Depends on how serious the engine is and how much money/time you want to spend on it.

For a typical street/strip SB or BB you just have to live with what you get. If you buy a good set of rocker arms then you'll be okay for .550 to .600 type lift.

If you're going to run more than .700 lift then you'll need to spend some time sorting it out. Once you get past .800 lift you'll probably need to switch to Jesel or T&D to get anything that will work.

For really high spring pressure you'll want to use the 2/3 lift rule rather than mid-lift. The 2/3 lift rule minimizes the amount of travel under load but the total scrub pattern is wider than the mid-lift method.


No, you do not have to live with what you get!!! Total nonsense. Rocker geometry has to do with way more than just the rocker arm, and any roller rocker that will fit the head can have correct geometry.



I agree you can get the valve side geometry pretty close by shimming and moving the fulcrum stand, you cannot do anything about the pushrod side unless the rocker is made for the lift and head in use. The last valve train issue I had involved the pushrod side and had to get rockers remade
Posted By: B3RE

Re: Valvetrain geometry......mid lift pushrod measurement - 01/29/15 04:46 PM

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Depends on how serious the engine is and how much money/time you want to spend on it.

For a typical street/strip SB or BB you just have to live with what you get. If you buy a good set of rocker arms then you'll be okay for .550 to .600 type lift.

If you're going to run more than .700 lift then you'll need to spend some time sorting it out. Once you get past .800 lift you'll probably need to switch to Jesel or T&D to get anything that will work.

For really high spring pressure you'll want to use the 2/3 lift rule rather than mid-lift. The 2/3 lift rule minimizes the amount of travel under load but the total scrub pattern is wider than the mid-lift method.


No, you do not have to live with what you get!!! Total nonsense. Rocker geometry has to do with way more than just the rocker arm, and any roller rocker that will fit the head can have correct geometry.



I agree you can get the valve side geometry pretty close by shimming and moving the fulcrum stand, you cannot do anything about the pushrod side unless the rocker is made for the lift and head in use. The last valve train issue I had involved the pushrod side and had to get rockers remade


Yes, I am addressing the valve side because the pushrods side is, as you mentioned, built into the rocker. I disagree that valve lift has anything to do with the rocker design, and outside of the valve angle and required offset, the cylinder head has no effect on rocker design either. The pushrod approach angle and the valve angle determines the adjuster placement for a given application. I have yet to see a "budget" type rocker be correct. This is the main reason I am working on my own rocker design.
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