Introducing Lykins Motorsports roller tip non-adjustable rocker arms....

[blykins]

I've been working on getting this done for the past several months and finally received some part samples from Harland Sharp yesterday. 

Some features:

*Bronze bushing fulcrum, with oiling passage to allow oiling from pushrods or from rocker shafts
*Lightweight aluminum body with full roller tip
*Hardened pushrod cup insert
*Will accept up to 700 lbs of spring pressure
*Uses readily available 5/16" ball/ball pushrods instead of having to rely on full custom 3/8" ball - 5/16" ball pushrods or 3/8" cup - 5/16" ball pushrods
*Works with factory diameter rocker shafts
*Same width as factory rockers to allow either use of factory stands or aftermarket billet stands
*Will work with spring spacers or solid spacers
*1.76:1 rocker arm ratio

The forethought for this revolves around hydraulic roller FE's.  I have customers that occasionally want higher rpm engines but they don't want to go with a solid roller because of the extra expense, maintenance, etc., and they don't want to go with a solid flat tappet because of camshaft break-in issues that occasionally plague us.  Hydraulic rollers are an excellent choice for street engines since they are basically an "install-and-forget" scenario:  no maintenance, no camshaft break-in, etc. 

In years past, we have seen a "brick wall" on rpms when it comes to the hydraulic roller camshafts and this is because of several variables:  camshaft lobe aggression, lifter choice, oil choice, and valvetrain weight.  If you use an overly aggressive camshaft lobe, then it's hard for the valvetrain and lifters to keep control of things.  If you use something like a Morel lifter, then the lifter component tolerances are much tighter and the resulting oil viscosity has to be eyeballed so that the lifters can operate the way they were intended to operate.  If you use a heavy valvetrain assembly, i.e. 3/8" stem, large headed valves, steel retainers, adjustable rocker arms, etc., then you have a lot of unnecessary weight that the lifter plungers are having to deal with.  Over the years, we have gone from seeing 5800-6000 rpm limits to 6200-6500 rpm limits and a little higher.  We have been able to get to those milestone points with FEs because we have been "slimming" things down and finding component relationships that work.  Less aggressive lobes are being used in correlation with higher-quality lifters, smaller stemmed valves, and the use of non-adjustable factory rocker arms.  I have routinely seen rpms of over 6500 and I do believe that Blair has had a few engines where he has seen 7000 rpm with a hydraulic roller camshaft.

I feel that the rocker arm choice is a big player in this as it can either help or hurt the valvetrain weight.  Adjustable rocker arms with large adjusters, jam nuts, etc., add unnecessary weight.  Unnecessary weight can make it harder for the lifter to do its job.  A lot of us have seen the results of using the non-adjustable factory rockers:  in engine combinations that have usually lost control of the lifters at around 6000 rpm, the lighter rockers allow the peak horsepower rpms to creep up by several hundred rpm or more.   Again, you have to look at the overall picture and choose a combination that works, but the rockers do play a large role.

However, there are constraints with the factory rockers.   The shoe style rocker tip leaves an undesired wider pattern on the valve stem and in extreme situations where we're using very small stemmed valves, that can pose a problem without adding lash caps.  The rockers themselves are not meant to carry large valve spring pressures or large valvetrain loads.   It's not hard to find good rocker cores, or even very nicely rebuilt pieces from companies like Rocker Arms Unlimited, but again, their original strength and design capacities can be quickly overran. 

The beauty of these rockers is that they are basically universal.  They will work as a "performance upgrade" to factory pieces by using factory shafts, stands, and springs.  They will also work as components of new systems, where they would be used in conjunction with new shafts, Precision Oil Pump billet stands, Precision Oil Pump spacers, etc.  They will work with hydraulic rollers, hydraulic flat tappets, and if careful consideration and measuring is taken in assembly, they can also be used with solid flat tappets and moderate solid roller camshafts.  We have seen recent instances where Cup engines use non-adjustable rockers so that spring pressures can be reduced and the rockers are used in conjunction with careful pushrod length measurements and/or lash caps.  There's no reason why this couldn't be completed with an FE solid flat tappet or solid roller camshaft to allow for lower valve spring pressures and lower maintenance intervals. 

I have also discussed several options with Harland Sharp, including needle bearing fulcrums (would require larger diameter shafts) and lightening programs which would further reduce the weight of the rocker arm. 

Overall, I'm very excited to get this going and will be doing some testing with them in the next several weeks.  I need to get a few customer builds dyno'd and delivered, which will free up some time for me. 

[garyv]

Congratulations on being able to pull this off.

garyv

[e philpott]

Great job Brent !!

[Falcon67]

Well done.  If I ever run an FE, this would be on my "must include" parts list.  I have a gazillion rounds on Harland 351C rockers without any issues.  Would not run anything else.

[winr1]

Nice !!

More FE stuff   :-)





Ricky.

[Stangman]

Nice Brent just another way we can get our FE motors to make more power and also be more reliable if all your test turn out good. And also I think Harland Sharps are a very good product. Good luck can’t wait to see some results.

[Drew Pojedinec]

Can I drill and tap them for adjusters
I do like my sft.

[afret]

Congrats on the nice new FE rockers! 

I have a question though.  The HS rockers tend to be pretty robust and is there a need to have rockers that can handle 700 lbs open pressure with a hydraulic roller cam?  Don't know much about them and how much spring pressure you need but I run only about 600 lbs open with a solid street roller.  Seems like if you can reduce that spec down to 550-600 lbs HS might be able to do some more weight reduction on that rocker and help you with lesser weight and still be pretty strong.

[TripleJ]

Very nice! Also very interested for my current build. Hopefully they will be available soon.

[blykins]

Congrats on the nice new FE rockers! 

I have a question though.  The HS rockers tend to be pretty robust and is there a need to have rockers that can handle 700 lbs open pressure with a hydraulic roller cam?  Don't know much about them and how much spring pressure you need but I run only about 600 lbs open with a solid street roller.  Seems like if you can reduce that spec down to 550-600 lbs HS might be able to do some more weight reduction on that rocker and help you with lesser weight and still be pretty strong.

Earl,

That's a valid question and something I have addressed with HS.  We can do some lightening programs to them, but as you know, it takes a lot of aluminum to really make a big difference in weight.  We may be able to change the weight slightly, but in my mind, I don't see any mind-blowing changes being available to us.  I actually had talked to Manton about making a set, but all of their rockers are tool steel only.  Their design was light because you can go with a smaller profile with steel, but the price was knocking on $1800 a set, rockers only.  Obviously that was way out of the market for this product. 

The main design goal for these was hydraulic roller use, where the average spring pressure that I run is 375 lbs open.   However, in times past, we've only been aiming for lower (relatively speaking) rpm usage.   To creep up past 7000 rpm, and even try a slightly more aggressive cam lobe, we'll be looking at over 500 lbs open pressure.   So your point is very valid in that respect.

The secondary design goal was to be able to use these on solid camshafts.  If someone is running a 600 lb open spring pressure currently with a solid roller, then there's no reason why they shouldn't be able to use these rockers with some very careful measuring and even aim to reduce the valve spring pressure that's needed. 

So yes, the rockers may be beefier than necessary....I suppose to their own fault....but it would allow the possibility of "trimming" for hydraulic use and extra beef for solid use. 

[Pentroof]

Nice stuff.

And Jay will be moving this to the Vendor Classifieds in 3...2...1...

[e philpott]

Nice stuff.

And Jay will be moving this to the Vendor Classifieds in 3...2...1...

Introducing of a new product , highly doubt it will get moved .lol

[Pentroof]

Brent,
Can you better illustrate the oiling path to the pushrod tip? I don't see an oiling port in the body. Is it just the picture, or is the oiling coming through the insert?

Another question: what is the method of fastening the insert? Press fit, threads?

Thanks.

[blykins]

Jim, the bushing has an annular groove that feeds the pushrod cup and the roller tip.  If you oil from the shaft, it feeds it all that way.  If you oil from the pushrod then it oils from that direction.  This is similar to the T&D streets. 

The pushrod cup is pressed in I assume.  That would be the only way to guarantee that the pushrod seat is located at the same depth each time.  The non adjustable rockers cost a little more to manufacture because of that fact, as each hole depth is critical.

[HarleyJack17]

I am curious on the pushrod insert as well.  On one hand press fit makes sense. On the other a threaded insert makes sense.  I had this same idea years ago but I am not in the business and never pursued it   The PR cup was the main hang up on my mind, figured it would be highly specialty where as the rest is common(in a sense).
Looks good and I am sure they are going to be a hit. Two thumbs up. 

[blykins]

Been at the dyno all day, so I've just had a chance to get back and take a closer look at things.  The pushrod cup is "splined" so I'm sure it's a press fit.   

[blykins]

Got some mockup done over the weekend.  Plenty of pushrod to rocker body clearance at .700" with a double tapered pushrod.  Geometry looks very nice as well.  With the stand height adjusted, I'm getting a small .050" wide contact pattern across the valve stem tip. 

[Dumpling]

Bolt on electric valves coming...


.https://www.msn.com/en-us/autos/enthusiasts/the-genius-way-theyre-about-to-reinvent-the-camshaft/ar-BBPpEq2?ocid=mailsignout

[RustyCrankshaft]

Bolt on electric valves coming...


.https://www.msn.com/en-us/autos/enthusiasts/the-genius-way-theyre-about-to-reinvent-the-camshaft/ar-BBPpEq2?ocid=mailsignout

Not really as new as that article makes it sound. Ship engines have been using camless technology for over a decade (like the Sulzer FLEX series of engines, although other have followed suite).

Cummins, Caterpillar and Ford have all had camless engines. It works, but so far usable RPM range is an issue. Similar to why electronic diesel engines and now DI gas engines have a similar issue at higher engine speeds. You run into latency and rate of injection issues. At least with a gas engine you can crutch the problem by running both DI and port injectors.

It would be really cool if they could actually make a camless engine live and make power at 6+.

As an interesting aside, Cummins also had a small fleet of engines that did not use any coolant a few years ago.

[WConley]

I think the gold standard of camless engines is the Koenigsegg "Freevalve" design.  It uses a direct actuator instead of those funny complex mini cams.  They've built demonstration engines that rev at F-1 rpms.

https://www.motortrend.com/news/is-the-era-of-the-camless-valvetrain-finally-upon-us-technologue/

[cjshaker]

I think the gold standard of camless engines is the Koenigsegg "Freevalve" design.  It uses a direct actuator instead of those funny complex mini cams.  They've built demonstration engines that rev at F-1 rpms.

https://www.motortrend.com/news/is-the-era-of-the-camless-valvetrain-finally-upon-us-technologue/

They've also been using the design in a couple of test cars for a couple of years now. Part of the issue with making it work is how the compression ratio changes through the RPM ranges, and how the actuators can reliably deal with that, especially at upper RPM ranges. If anyone will get it to work, I think Koenigsegg will. Regardless, I don't think any of this will affect us FE guys. We're still going to need rockers like Brents.

[Heo]

I think it is far into the future before someone make a freevalve conversion kit for a FE
I with Doug on this that koeningsegg is the one that can make it work. I have been close
to the factory a few times but always at night time. I would like to stop by and ask if one
could get a factory tour

[cjshaker]

I think it is far into the future before someone make a freevalve conversion kit for a FE
I with Doug on this that koeningsegg is the one that can make it work. I have been close
to the factory a few times but always at night time. I would like to stop by and ask if one
could get a factory tour

A factory tour would be pretty cool. Talking them into a test drive would be even cooler! Taking along the wife, dressed in that leopard skin outfit should help.

[Heo]

I think it is far into the future before someone make a freevalve conversion kit for a FE
I with Doug on this that koeningsegg is the one that can make it work. I have been close
to the factory a few times but always at night time. I would like to stop by and ask if one
could get a factory tour

A factory tour would be pretty cool. Talking them into a test drive would be even cooler! Taking along the wife, dressed in that leopard skin outfit should help.

  You think so?  

[Cyclone03]

Brent, When and how much ? I'm very happy with my non adjustable "shoe" set up with the Cam you speced me in Apr. A little more lift might be nice.

[blykins]

Brent, When and how much ? I'm very happy with my non adjustable "shoe" set up with the Cam you speced me in Apr. A little more lift might be nice.

You can email me for pricing, or I can put an ad in the vendors' classifieds section. 

I have more sets coming after the initial set for me to inspect.   They should be here in the next week or so. 

[Tobbemek]

What is the weight of them and of the OEM non adjustable?

[blykins]

I weighed a couple non-adjustable factory rockers that I have here and they weigh around 99-100g. 

My rockers weigh 140g, but the bronze bushing makes up a chunk of that, as it weighs about 40g just by itself. 

[Tobbemek]

I know its complicated to calculate the need of valve spring pressure of a certain combination of valve train ,cam and so fourth and how different rockers affect the math.
I have been looking fore it in over 20 years and every time i found something the math is just to complicated, way over my education

“Mass is a measure of how difficult it is to get something to move in a straight line, or to change an object's straight-line motion. The more mass something has, the harder it is to start it moving, or to stop it once it starts. Similarly, the moment of inertia of an object is a measure of how difficult it is to start it spinning, or to alter an object's spinning motion. The moment of inertia depends on the mass of an object, but it also depends on how that mass is distributed relative to the axis of rotation: an object where the mass is concentrated close to the axis of rotation is easier to spin than an object of identical mass with the mass concentrated far from the axis of rotation.
The moment of inertia of an object depends on where the axis of rotation is. The moment of inertia can be found by breaking up the object into little pieces, multiplying the mass of each little piece by the square of the distance it is from the axis of rotation, and adding all these products up”

9.1.5 Valvetrain inertia force

Valvetrain inertia force is affected by component mass and valve acceleration. In the simplified single-degree-freedom valvetrain dynamics model (detailed later in Fig. 9.15), the inertia force at the valve side can be calculated as the product of the valvetrain equivalent mass and valve acceleration. The valvetrain equivalent mass usually can be calculated as follows:
9.4mVT≈mvalve+mretainer+mbridge+mspring3+mRA⋅lRA,02lRA,ValveSide2+mpushrod3fRA2

where mvalve is the valve mass, mretainer is the retainer mass, mbridge is the valve bridge mass, mspring is the valve spring mass, mpushrod is the pushrod mass, mRA is the rocker arm mass, lRA,ValveSide is the rocker arm length at the valve side, fRA is the rocker arm ratio, and lRA,0 is the radius of gyration. The effective mass of the rocker arm can be considered as the mass of the rocker arm concentrated at one point which is at a distance lRA,0 from the center of rotation, i.e., IRA = mRAlRA,02 where IRA is the moment of inertia of the rocker arm with respect to the center of rotation. Lower cam acceleration, higher stiffness, lower weight, and higher natural frequency of the valvetrain result in lower vibration amplitude of the valve acceleration. The design guideline for valvetrain inertia force control is that the design needs to achieve a precise target of valvetrain no-follow speed with an optimized gas load. Neither over-design nor under-design is acceptable for a good balance between breathing performance and valvetrain dynamics.

My conclusion is to trust what reliable engine builders com up with works and there experience what docent work in particular application/combos .

[blykins]

Your first paragraph that you quoted sums it up pretty well.   Figure skaters can demonstrate this when they raise up on the fronts of their ice skates and spin on axis.  When they tuck their arms close to their bodies, they can easily spin at a higher rpm.  You can do it in an office chair as well.  Have someone spin you around with your arms out, then see how quickly you accelerate when you tuck your arms/legs in.  That's why I don't mind that a big chunk of my rocker arm mass is in the bushing.

The FE valvetrain system has several obstacles to overcome when it comes to higher rpm operation.  Factory 3/8" stem, large headed valves don't help and neither do rocker arms with the large adjusters/jam nuts hanging way out away from the shaft/rocker arm centerline. 

If you look at some other engine platforms that will easily spin to 7000-7500 with hydraulic rollers, you will see the differences:  lighter valves, lighter valve springs/retainers, and either non-adjustable rocker arms or rockers that are stud-mounted, so that the adjuster (poly-lock) is on the centerline of the rotational axis.

It's easy to see the affects of a lighter valve spring or a titanium/tool steel retainer on rpm before valve float and a lot of guys know to try and lighten the valve side up to get away from that limit.  Lightening the other side of the rocker arm is just as important. 

We have been using non-adjustable factory rockers for years but their design doesn't account for extreme valve spring pressures or extreme rpms. 

[Tobbemek]

The problem is not that i don't understand whats going on with inertia and mass and centrifugal forces and how the adjusting screw and nut on the FE mechanical rocker arm affects vs non adjustable rocker.  Ore the lifter is lofting because not stiff enough push rod and so on. There is plenty of articles on the subject including spinntron tests.     I think we all do understand this part moor ore less on the forum.

Its the calculation part, the math that's out of reach,   fore me anyway.
So if you have that part figured out please bee so kind and enlighten me. 

[cjshaker]

Its the calculation part, the math that's out of reach,   fore me anyway.
So if you have that part figured out please bee so kind and enlighten me.

Not too many car guys are NASA level engineers, trained in the mathematics of inertia/load etc. Not saying Brent isn't capable of that, he's a pretty smart guy, but that's pretty complicated stuff that has a hundred parameters that affect outcome. Rather, most of this stuff comes from observation and experience based on repetition, or the experience of others that share their data about valve float given certain combinations or ramp design, valve and retainer weight, rocker weight (which, like Brent pointed out, isn't about total weight, but rather the weight that extends outside of the rotational axis) etc. When you have a collective knowledge that shares info, like has happened on the FE forums over many years, with many shared dyno experiences, you just form a basis of knowing what might/will work and what might/will not. I'm pretty sure the engine guys on the forum will readily admit that their knowledge base grows with every engine they build, not some set mathematics formula. That's one of the great things about the 'dyno' page on this forum. It's a great place to compare combinations and see what really works well together.

[blykins]

Its the calculation part, the math that's out of reach,   fore me anyway.
So if you have that part figured out please bee so kind and enlighten me.

Not too many car guys are NASA level engineers, trained in the mathematics of inertia/load etc. Not saying Brent isn't capable of that, he's a pretty smart guy, but that's pretty complicated stuff that has a hundred parameters that affect outcome. Rather, most of this stuff comes from observation and experience based on repetition, or the experience of others that share their data about valve float given certain combinations or ramp design, valve and retainer weight, rocker weight (which, like Brent pointed out, isn't about total weight, but rather the weight that extends outside of the rotational axis) etc. When you have a collective knowledge that shares info, like has happened on the FE forums over many years, with many shared dyno experiences, you just form a basis of knowing what might/will work and what might/will not. I'm pretty sure the engine guys on the forum will readily admit that their knowledge base grows with every engine they build, not some set mathematics formula. That's one of the great things about the 'dyno' page on this forum. It's a great place to compare combinations and see what really works well together.

That's probably about as good as I could put it. 

I'm a degreed mechanical engineer, but the amount of statics/dynamics involved in calculating something like that would be extremely in depth and would probably be only done accurately with the help of FEA software.

In some cases, it's easier to just try things on the dyno, or on the Spintron.   

I built a 556 cubic inch BBF pulling truck engine for a customer that essentially had an operating rpm range of up to 9000 rpm.   I had contacted my Comp rep as well as my Trend rep to see about taking my camshaft/heads/etc. to them and spending a day on the Spintron.  Unfortunately, neither one of them had a BBF block there with 60mm camshaft journals.  Comp used to have one but Kaase took it home (thanks Jon...).   

The Spintron takes a special block that has basically been cut up.  There is no rotating assembly involved; it's essentially just an empty block with a camshaft in it, topped with heads and valvetrain, driven by an electric motor.  The valvetrain is spun up to whatever rpm levels are required and data is collected to see what changes need to be made.  I'm sure Mr. Conley could fill us in and speak more at length about it. 

Since the Spintron was not available to me, I got on a conference call with my Comp rep and one of the higher-up design guys and gave them every single bit of information that I had, down to the weight of the valve locks......weights of the lifters, valve springs, valve spring pressures at install height, rocker arm weights, rocker arm materials, pushrod lengths and diameters, valve sizes and weights, etc, etc.  Once all the data was given, the phone call was ended.  I received an email a few days later stating that the camshaft lobes that I had selected, in combination with the valvetrain parts that I was using, was capable of 10500 rpm. 

Sometimes it takes experience and lots of data collection to find something that works and works well.   

[Heo]

Well math is good but in the end of the day you dont know
if it works before it is tested, even if the math says it will or wount

[blykins]

Well math is good but in the end of the day you dont know
if it works before it is tested, even if the math says it will or wount

That's the first thing they teach you in engineering school....

[Heo]

Well math is good but in the end of the day you dont know
if it works before it is tested, even if the math says it will or wount

That's the first thing they teach you in engineering school....

Yes i know i went to that school my self.  In those days when calculating the strenght
on some plain construction. Your calculated strenght x3 to get the right safety marginal
X6 on traverses and lifting equipment like that. It meant that you ended up pretty close
to what you had used if you had guessed with out calculations