[Jeff260z]

I think I'm going to look into making some. I haven't stripped my spare motor yet but I'll get around to it this winter. I used to work as a CNC machinist and some good friends still have access to four CNC machining centers and a CNC turning center. A few cases of beer and almost 1.5 million dollars worth of tooling should be able to accomplish something.

I wouldn't have quit my job there if I had found my Z sooner. It makes me sick just thinking of all the stuff I could be making there on the weekend for my Z.

If I make a set, are the any testers willing to risk catastrophic engine damage?

Maybe I'm just dreaming but I'd like to free up 20 hp or so. Who wouldn't?

 

[yo2001]

make me a 1.6 ratio rocker arms. I'll try it. I guess

 

[McAdam]

send me some, I'll give it a shot.....

sounds like fun, Email me with details....

 

[JT240Z]

I'm in. I've got an L28 with an E31 head I'm willing to try this out on. E-mail me.

 

[Zuber]

Nothing personal here, but, who wants to put experimental rockers in their engine? I guess if you don't care at all about your engine, and don't care if it self destructs, you would be interested. Think about it for a second people. If a rocker goes, it will not go quietly. Chances are it will take out a lot of other stuff with it.

I (and I'm sure many others) would rather the inventor tries it out on his own engine, and give a report on the findings. Things break. If not properly engineered, things break quickly. He hasn't even mentioned what material he will use, and there are already three people lined up for "free parts".

Have a little more respect for your engine, folks.

 

[jeffp]

The idea is good, you will need to totally redesign a cam to go with a roller rocker setup, and you will have to redesign the rockers also. I use to work for sigErosn and made this kind of stuff. You would be best served making a mold of the new rocker configuration and then machining it to specs to fit the roller in the tip and the cam contact area. Or you could just make the roller bearing for the can area, and you would still have to regrind a new bump stick for it as well. If you design a roller for the valve face and lash pad area you could run into problems loosing lash pads, and I dont think you would want to try running without lash pads. In that case you would want to design a new spring retainer also to bring the top of the valve up out of the retainer so the roller could contact the valve properly.

You know all of this stuff is doable, but if you had to pay somebody to do it now we are talking some money.
The big challenge is the rocker it's self. there really is not enough material to install a roller bearing in the tip of the part, and it really is not wide enough to install a roller bearing in the body of the part, so a redesign of the rocker is almost a given. You know when comp cams first started making their rockers they had a part that had the roller in the tip only for the valve, maybe that would be the best thing to try first. Sounds like a challenge to me.

 

[Dan Baldwin]

I believe this has been done. Talk to Dave Malvern at Malvern Racing, a real wizard. Tain't cheap, nor easy. TONS of things you could do for less cost/effort/time to make more power.

Dan Baldwin
'71 240Z 3.1
COMSCC #7 SPB

 

[zbyter]

Re: SigErson/Mallory

Hey,
I used to work for SigErson/Mallory in Carson City Nevada. When did you work there and in what department? I was in the Specials department. I also rotated into many other positions as needed. Let me know, we may know each other.
zbyter

 

[kjones]

Look here about Malvern and rolloer rockers

To all,
I spoke to Dave Malvern a few months back about this... He basically said that he spent a lot of time and money on this project and was never able to get it to work properly. I'll quote him as saying "Someone should have talked me out of this project because it has driven me nuts"

Having said that, he surely has lot's of experience with this and has gone through the heart aches of design failures. BUT he did say that he had a customer running a L28 motor in a boat that was able to get it running for a short time before it blew up and it was able to do 10,000 rpms!!! He said it was fun while it lasted... LOL

Now I guess the question is, is it worth the time/money to design and test?

The benefits would be great and provide a new source of power and flexibility to Z engine builders, but the cost of research and development is probably too high for a limited market... that's why it hasn't been done before. Is it possible? I'd say yes... Is there a market? Maybe... If the SCCA or other racing organizations allowed them to be run, then I'd say there is a "small" market. Would I love to get my hands on a set? YOU BET!

Some other things to consider... The stock pistons/rods/crank would not hold up at these high rpms... Fuel delivery becomes an issue... When it's all said and done with an aftermarket Engine management system ($3,000+), new engine internals ($appx +$4,000), plus all the "extra's" you'd need for the drive train etc... it would be very expensive. Plus the roller rocker "kit" including a new custom grind cam is probably another $1,500+...

So... Is it worth it? Put me on a list of "testers". I have a spare engine I'd be willing to sacrifise...