Hydraulic roller lifters !

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JBR-3 wrote:Another project I have will be a 540-inch pump gas street motor with a Richmond 6-spd.
Can't really shift the Richmond above 6500, boxing in the engine RPM range. Figure peak HP at around 6000, shift around 6500 tops.
6500 is also a reasonable limit for a hydraulic roller cam.
Heads will be modified B-460 heads (old).
By Manley, a 5.65x2.35 titanium valve is about 100 gm. A small block chev 2.02 stock length Severe Duty valve is about 111 gm.
Similar weight advantage on exhaust valve comparison.
I already have some good Ti valves for this application (and was considering a re-application of some hi-temp surface coatings).

Bearing in mind advice by Randy Malik on the problems with the sideways swiveling of stud-mounted rockers caused by pushrod angularity,
I think I can minimize this effect, and successfully use hydraulic roller lifters.

So here is my question: What is the LEAST amount of valvespring pressures I could use for long term reliability ??
This would assume a cam probably at most .650" lift with easy ramps. Peak horsepower really of no concern, it's just
a torquey street motor. (Of course under-utilizing some of the components !)

Compared to an SBC, the big Ford's pushrods would be a little longer and the rocker arms weigh a little more. Other weights
of valvetrain components would be lighter on this Ford.

This is pretty much strictly a valvetrain dynamics question. Valvetrain doesn't know what's going on underneath it.

I build a lot of BB Chevs with 5.50" long, 2.30 steel valves that see well over 7000 with hyd. roller lifters. The 2.30 valves I use are 142g.
Hyd roller lifters are considerably taller than non roller lifters and that helps shorten the push rod.
I've heard about the "sideways swiveling" of the Ford as if it's unique to that engine. The next 385 series I do I'm going to have to really look at this. The BB Chev has more compound angles to the pushrods than the BBF and the pushrods are shorter which would seem to make any sideways movement even worse. In my mind's eye I can't see the Ford being any worse or that much different than the Chevy as to make it so difficult for hyd. rollers to be used and work just fine. Not saying it isn't true, just saying I have a hard time visualizing it. I have BB Chev hyd roller engines that turn 7800 rpm with >.760" lift and 260# seat pressure, that big 142g valve and aluminum stud mount rockers. Seems what you're wanting to do should be a walk in the park. I will also say you don't need any where near a 2.35 valve for a 540ci engine turning 6500. Spring pressure will depend on the lobe but usually in the 150-160 range, 450-ish open should work for something like you're doing. Less is not always more when it comes to spring pressure.
JMObservations

Shaft or Bolt-down fulcrum rockers, (like the Yella Terra rockerss), will alleviate the sideways motion at the roller tip.

Otherwise ... don't use a hydraulic roller lifter in any BBF expectant of long term valve guide reliability.

A Richmond 6 speed? Why? Use a T56 magnum.

rmcomprandy wrote:Shaft or Bolt-down fulcrum rockers, (like the Yella Terra rockerss), will alleviate the sideways motion at the roller tip.

Otherwise ... don't use a hydraulic roller lifter in any BBF expectant of long term valve guidex reliability.

x2

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why not just use a tight lash solid roller?

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I've been hearing about hydro roller lobes on billet cores using a solid roller lifter...lash is around .005 .008

Why bother with a hyd roller in a bbf. What waste of time,and money.

BOSS 429 wrote:Why bother with a hyd roller in a bbf.   What waste of time,and money.

Must be a real POS engine if that's the case.

Scott Foxwell wrote:
Must be a real POS engine if that's the case.

why dont you explain why its a good idea to use a hyd roller lifter in a BBF over a solid roller?

BOSS 429 wrote:

Scott Foxwell wrote:
Must be a real POS engine if that's the case.

why dont you explain why its a good idea to use a hyd roller lifter in a  BBF  over a solid roller?

Four major reasons to use a hyd roller over a solid on any engine.
1) Roller never loses contact with the lobe. Benefits should be self explanatory.
2) Hydraulic internals act like a shock absorber and absorb a lot of valvetrain harmonics. Again, benefits should be self explanatory.
3) No "jack hammer" effect with stud mount rockers, where lash is taken up at the stud and trunnion.
4) Pushrods are shorter. Shorter pushrods, especially on a tall deck engine, are lighter and stiffer.
Now days we have hyd. lifters that we can run solid roller lobe profiles and spring pressures on. If you have to go to shafts on the BBF to eliminate some sort of geometry issue (which I still don't buy) then so be it but the benefits of the hyd. roller lifter are universal and absolutely not a waste of time or money.

BOSS 429 wrote:Why bother with a hyd roller in a bbf.   What waste of time,and money.

It works fine from my expriance, but don't use cheap parts.

dfree383 wrote:

BOSS 429 wrote:Why bother with a hyd roller in a bbf.   What waste of time,and money.

It works fine from my expriance, but don't use cheap parts.

What?? Like you're the "Horsepower and Torque King" or sumfin' ??

http://www.hotrod.com/articles/572ci-ford-big-block-built-to-eat-rat-motors/

rmcomprandy wrote:Shaft or Bolt-down fulcrum rockers, (like the Yella Terra rockerss), will alleviate the sideways motion at the roller tip.

Otherwise ... don't use a hydraulic roller lifter in any BBF expectant of long term valve guide reliability.

For clarification...from the article....


“I don’t know how long I would trust them on the street,” Freelander said,

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dfree383 wrote:

BOSS 429 wrote:Why bother with a hyd roller in a bbf.   What waste of time,and money.

It works fine from my expriance, but don't use cheap parts.

With how many have you had experience where they were to be rum more than 1,000 miles ...?

They certainly do work ... until the guides or valve stems start to wear.

dfree383 wrote:

BOSS 429 wrote:Why bother with a hyd roller in a bbf.   What waste of time,and money.

It works fine from my expriance, but don't use cheap parts.

Nice build and really good power but did I read correctly that you had a 2.25 intake valve in those heads and 3/8 pushrods??
I can see on way to really help the valve train issues and that would be to have a stepped guide plate and get the "fork" closer to the rocker. That would go a long way to help reduce the side to side movement of the rocker.

cletus66 wrote:

rmcomprandy wrote:Shaft or Bolt-down fulcrum rockers, (like the Yella Terra rockerss), will alleviate the sideways motion at the roller tip.

Otherwise ... don't use a hydraulic roller lifter in any BBF expectant of long term valve guide reliability.

For clarification...from the article....


“I don’t know how long I would trust them on the street,” Freelander said,

I believe that in reading the whole article that was in reference to the bronze lifter bushings and nothing to do with the valve guides.
The complete quote:

He also opted for bronze lifter bushings since he planned to recycle the engine into his dragster, and bronze is so much more forgiving. “I don’t know how long I would trust them on the street,” Freelander said, “but the lifters looked brand new after 80 to 90 dyno pulls.”

Why not increase valve stem diameter? Thought just occured to me if you increase valve stem diameter then you increase contact point of rocker before it imparts side loading and you also increase contact area if side loading does occur spreading load over a larger area. Maybe it is a wild idea that has no merit.

SandHillsHillbilly wrote:Why not increase valve stem diameter? Thought just occured to me if you increase valve stem diameter then you increase contact point of rocker before it imparts side loading and you also increase contact area if side loading does occur spreading load over a larger area. Maybe it is a wild idea that has no merit.

Supposedly it's the side to side wiping motion of the rocker that causes premature guide wear, not the contact point. The angle of the pushrod changes as the valve opens and closes. It chages on two axis; left and right, forward and aft. The forward and aft movement are kept linear by the guide plate and in the direction of the roller tip. Excessive sweep with the roller tip (when pushrod length is incorrect) can cause excessive guide wear even if the pattern is perfectly centered. Proper rocker geometry will minimize the sweep pattern and reduce guide wear, even if the sweep pattern is off center of the valve tip. There is also a side to side movement of the rocker and this puts a side load on the valve as it opens and closes. The guide plate is the pivot point for this side to side movement where the pushrod acts like a lever and unfortunately there's not much you can do about that. You can eliminate the guide plate so that the rocker end of the pushrod is free to follow the rocker but that means shaft mounted rockers or valve- tip guided rockers which would really exaggerate the valve stem wear. My guess is this is where the bad reputation came from because this phenomenon occurs with every canted-valve valve train ever made. The other thing that would help is getting the guide plate closer to the rocker and minimizing the lever effect that the pushrod has on the rocker. That would slow down the side to side movement of that end of the pushrod.
JMObservations.

Scott maybe I shouldn't have mentioned contact point. What I am really thinking is the sideload forces placed on the guide by the valve stem. If you increase the diameter of the stem you increase the width of the tangent point when the sideloaded stem exerts forces against the guide. This increased contact area spreads the load out more that the guide actually sees. Easier to think of in exaggerated terms. Say the original stem diameter was only 1/8" and side loaded it with 100 pounds. Think of the what the pounds per sq inch would be now change the stem to 3/8" and apply the same 100 pounds of side load, you have decrease the load per sq inch of area on the guide. With the decreased load the guide sees by switching to 3/8" from 11/32" it may be enough that the guides survive.

SandHillsHillbilly wrote:Scott maybe I shouldn't have mentioned contact point. What I am really thinking is the sideload forces placed on the guide by the valve stem. If you increase the diameter of the stem you increase the width of the tangent point when the sideloaded stem exerts forces against the guide. This increased contact area spreads the load out more that the guide actually sees. Easier to think of in exaggerated terms. Say the original stem diameter was only 1/8" and side loaded it with 100 pounds. Think of the what the pounds per sq inch would be now change the stem to 3/8" and apply the same 100 pounds of side load, you have decrease the load per sq inch of area on the guide. With the decreased load the guide sees by switching to 3/8" from 11/32" it may be enough that the guides survive.

I gotcha!