Roller rocker arms for Z ?

[PalmettoZ]

 

 

I recently replaced the cylinder head on my friends 98 Ford Ranger truck and discovered how close the ford roller rocker was to a L6 Z rocker.

 

It started me thinking that maybe this one could be modified or possibly making some on a CNC mill. It could really free up some horsepower with valve train friction reduction. What do you guys think?

[jeffp]

I have a set of roller rockers that were installed and run on the L engine. I havent really started to build a cylinder head, but I have all of the information to build a setup.

I also want to go with a roller cam, and that is the hard part, getting the cam with the cam ground to specifications. I also decided on getting the bearings roller Nascar style. I do have to build the towers and get the bearings, but I have all the design specs ready to build a head.

 

Anyway, yes it is possible, and it has been built before, so go for it.

[PalmettoZ]

Thanks-

 

By the way, did the photos go thru ? I cannot tell since I can't view them at work due to the firewall. What kind of roller rockers did you use ? I would think that a regular cam would work, although I have seen the profiles on roller cams before and noticed that the are alot rounder.

[roye@hrewheels.com]

The hardned roller bearing on the rocker will destroy the factory cast iron cam. You alway have to use materials of the proper hardness when using roller rockers (or lifters in a sbc/sbf). Call schnieder cams in san diego CA, they will grind a roller cam for an L-series.

 

RE

[PalmettoZ]

Thanks RE-

I am sure that the Datsun cam lobes has hardened surfaces, I don't know to what Rockwell hardness that it is though. I would not think that they are cast iron as well, but probably steel with a high carbon content so that they can be heat treated and hardened.

 

Of course the 2 hardened metals need to be close in hardness in order not to wear prematurely.

 

Has anyone been down this road before ? Thanks-

[roye@hrewheels.com]

Use a sbc as an example, roller lifters will take out a stock material cam, and a roller cam will take out the distributor drive gear if it is not replaced with a different material. Nissan/Datsun has always had good metalurgical practices but I am 95% sure that you will find that the surface hardening on a factory cam is not sufficient for use with a roller rocker.

[roye@hrewheels.com]

Of course if you want the anwser from the source, call schneider. They have stock regrinds for datsuns as well as fresh billet to produce whatever your heart wants. Some one there will be able to give you the full story, they have experiance with our cams and every other manufacturers. I'm not promoting them because they are local, but because they have always had a good reputation and they have helped my previouse employer out before on some weird applications.

 

RE

[Tony D]

Jeff P already stated he has done the homework, the hardness of the lobes, the proper profile.

 

Like he said, 'it has all been done before'...

 

There are several cam grinders in SoCal that will grind a roller cam profile, and know how to do so. There are a couple that will even take the time to explain the process in detail. Including the steps needed to turn a Nissan core into a suitable core for grinding a roller profile onto it.

 

Malvern Racing had roller cams and roller rockers available for the L-Engine. Dave has passed away, and his roller cam, roller follower information/developmental work was sold to a buyer on e-bay. The thread concerning that transaction is in the archives here at Hybrid Z.

 

BTW, I don't see anything but red 'x' for the photos, so maybe they didn't go through.

[katman]

Jeff P already stated he has done the homework, the hardness of the lobes, the proper profile.

 

Like he said, 'it has all been done before'...

 

There are several cam grinders in SoCal that will grind a roller cam profile, and know how to do so. There are a couple that will even take the time to explain the process in detail. Including the steps needed to turn a Nissan core into a suitable core for grinding a roller profile onto it.

 

Malvern Racing had roller cams and roller rockers available for the L-Engine. Dave has passed away, and his roller cam, roller follower information/developmental work was sold to a buyer on e-bay. The thread concerning that transaction is in the archives here at Hybrid Z.

 

BTW, I don't see anything but red 'x' for the photos, so maybe they didn't go through.

 

Yup, Malvern had done it, and Don Potter has done it. Potter used to say that it took 75 hp just to drive a stock Z cam at 5000 rpm, so imagine the potential once you eliminate most of that drag. Of course with the geometry change going from rocker to roller it requires a custom grind, which both guys had worked out. And Don was especially good with the metallurgy. Not sure how Don is doing, or if he's still alive. The "cheerful curmudgeon" was poster child for a heart attack.

[Guest Toddski555]

Does any body know were to get some roller "L" rockers.If not does anybody have any pictures of the ones that were produced at one time.

Thanks,

Todd

[PalmettoZ]

Does any body know were to get some roller "L" rockers.If not does anybody have any pictures of the ones that were produced at one time.

Thanks,

Todd

 

 

Hey Todd-

If you go to my cardomain site, there are pictures on the second page of the Ford Ranger 4 cylinder rocker arms next to a Datsun L6 rocker arm.

 

I did not try these on the head, I don't really think that they will fit. I would like to find a source as well of someone who sells roller rockers and roller cams as a package.

[Tony D]

How much are you guys who 'want to find them' willing to spend?

 

Forgive me, but talk is cheap. It would have to come as a complete setup, rockers, cam towers, ground cam, perhaps even as a complete head.

 

Are you willing to spend $1500+ for a cam setup alone, with no warranty? And that would be at a break-even point for the setup, not amortizing development costs, etc...

 

How about $3000+ for a complete head?

 

If not.... you are learning why there is limited aftermarket support for these types of components, as well as the parts that are quality, and are available, cost as much as they do!

[JMortensen]

How much are you guys who 'want to find them' willing to spend?

And what are you going to get after going through all the hassle to run them? How many hp is this going to free up? Especially when you're on a site where people swap in V8s and big turbo motors, spending all this $$$ on roller rockers on an L series just doesn't make a lot of sense from a hp to $$$ perspective.

[PalmettoZ]

How much are you guys who 'want to find them' willing to spend?

 

Forgive me, but talk is cheap. It would have to come as a complete setup, rockers, cam towers, ground cam, perhaps even as a complete head.

 

Are you willing to spend $1500+ for a cam setup alone, with no warranty? And that would be at a break-even point for the setup, not amortizing development costs, etc...

 

How about $3000+ for a complete head?

 

If not.... you are learning why there is limited aftermarket support for these types of components, as well as the parts that are quality, and are available, cost as much as they do!

 

Hey Tony D-

 

You are right, talk is cheap and I am just babling. I think what I was originally looking for was if someone had used roller rockers from another cylinder head type (such as the Ranger) and would they work with a normal cam.

 

Those questions are already answered, and no I would not want to pay 1500 for a cam set up or 3K for a complete head. Just flipping over rocks to see what is available. I haven't seen anything advertised for roller rockers for an L6.

[Tony D]

would they work with a normal cam. I haven't seen anything advertised for roller rockers for an L6.

 

That's a resounding no. The cam profile and metallurgical composition is much different in a roller cam, as well as the profile.

 

As stated above, there 'once' was a vendor, but he passed on, and his developmental work was sold to someone doing the research on his own, in private, at his own cost.

[Guest Toddski555]

I would like to reproduce these rockers because I own a machine shop and I would like to make more than one set to offset the costs. However I would still need the cam info.

Is there a complete head out there already set up? I already have some bucks in this motor and have eaten a couple of cams.

Thanks,

Todd

[BRAAP]

I’m curious, if you don’t mind sharing, 1) how much, and of, 2) what gain are you expecting these roller rockers will afford vs the current design?

 

Are you trying reduce valve train friction for better fuel efficiency? Take advantage of more aggressive ramp rates allowing more lift under the curve for a given lobe profile, (more power with less compromise in drivability?)

 

Jon already brought up the question, is it really worth the time, money, and effort for how much gain in what area, not taking into account the amount of research and development required that will allow you to take advantage of what roller rockers offer?

I’m assuming the perosn Tony mentioned that has done this, has been able to meet or exceeded OE valve train geometry, stability, and durability with these roller rockers?...

[PalmettoZ]

I would like to reproduce these rockers because I own a machine shop and I would like to make more than one set to offset the costs. However I would still need the cam info.

Is there a complete head out there already set up? I already have some bucks in this motor and have eaten a couple of cams.

Thanks,

Todd

 

 

Hey Todd-

I think it's great that you want to try to fabricate some rockers on your own, not much positive feedback coming our way on the post. If I had access to a mill I would like to play with trying to fabricate one. It's not rocket science in my opinion, and you can probably get schneider or even Webcams to grind you a roller cam with a base circle of your choice.

 

I know that Webcams uses a nitriding surface hardening process on their cams, and they could let you know the rockwell hardness of that surface. I think that as long as it is as hard or harder than the roller you would be OK. The metallurgy is not that difficult to figure out.

 

You might could take that Ford ranger rocker and fabricate one just a little longer, and center the roller under the cam to see how it looks. Probably you could use the roller out of that piece as well. It is a pretty close match to a Datsun rocker in size.

 

I don't think there is a complete head out there that anyone wants to share info on, otherwise that info probably would have surfaced already.

[BRAAP]

Hey Todd-

I think it's great that you want to try to fabricate some rockers on your own, not much positive feedback coming our way on the post. If I had access to a mill I would like to play with trying to fabricate one. ….

 

Thank you for pointing that out. We are being a bit finicky aren’t we?

 

There are times and projects that from a practicality stand point, don’t make much sense, but that is no reason not to pursue the project for personal reasons. I know of a few projects that fit that description more so than this topic, one in which I’m working on myself that has not practicality to it whatsoever, but I still have a desire to go through with it anyhow.

 

I guess what I’m saying is, I ‘m sorry for being so insolent in my previous post.

 

 

…

I already have some bucks in this motor and have eaten a couple of cams.

Thanks,

Todd

 

 

Todd,

So your engine is eating cams? Am I understanding this correct in that and you are wanting to convert to roller rockers in an effort to keep that from happening, or is it that you just want to tackle such an endeavor because you can/want to, etc?

 

If your engine is eating cams, there is something amiss that shouldn’t require the use of a redesigned rocker/cam interface. The OE valve train is actually quite robust, very durable, and proven itself for hundreds of thousand of miles even with poor oil maintenance etc. If an L-series is eating cams, something is being overlooked as it should not be eating cams. Here are a few things that cause the L-series cams to eat their lobes;

 

1) Improper cam wipe pattern. The cam lobe is essentially wiping of one end or the other of the rocker. Verifying cam wipe pattern on each and every rocker is imperative, especially if using and aftermarket cam and after the head been overhauled/rebuilt. This is the most common reason.

 

2) Lack of lubrication. Clogged spray bar port/s in an externally oiled system or someone installed an externally oiled cam with cam towers for internally oiled cam, (the lobes aren't getting oil).

 

3) Lack of Zinc in modern motor oils is a hot topic recently, especially for flat tappet cams. The domestic V-8’s with flat tappets are more susceptible to cam failure due to this vs the L-series with the V8’s need to “rotate” their lifters.

 

4) Soft cam cores as used by some aftermarket cam manufactures. I’m not so sure that these failure aren’t a combination of lack of Zinc AND the soft core, as we seem to be seeing more and more failures now than we used to 15 odd years ago, or at least people are talking about it more lately?...

 

Anyhow, just throwing that out there incase it might help.

 

Good luck with your project,

Paul

[Guest Widebodys30]

I would certainly agree that the base circle of the roller would change the events dramatically at the valve, granted.

 

However, I am very surprised to hear the consensus here is that the roller cams need to be of a HIGHER Rockwell value. I can't seem to understand the why. Why would a lobe that has a WHEEL ROLLING over it need to be harder then the stock cam that has a rocker that SLIDES metal to metal? Isn't the REDUCTION of friction(thereby wear) the whole point of a roller?

Yes, Higher lift cams are a byproduct of this.

 

And, 50-75 HP on these engines is STILL 50-75 HP...

 

Even a 400HP Turbo motor could use that, couldn't they?

 

I SALUTE you for your AWESOME observation,

and creative thought process, MYSELF.

 

The very best luck to you, if ya give it a shot!!

 

Get a kit reasonable and reliable, and lemme know!