Roller Rocker arm Pics

[Dadandson]

Here is a picture of the completed roller rocker arms I designed. Any and all comments are welcome, no encouraged!

 

[blkcorvair]

Looks great. How do you mean you designed them? Whats the ratio?

 

[Dadandson]

I am not sure I understand ratios. I used solid models in my CAD system and dimensions from the OEM arms to create an additional .040" of valve movement. Of the forty hours I spent on the head, 10 were in front of my CAD system.

 

[blkcorvair]

Oh so you mean you really designed them! I thought maybe you cross fit something else. Major

 

[Dug]

Tim,
Very cool. Did you use 2024 or 7075 for the arms? What material did you use for the roller? how hard (RC) did you go on the rollers? Very nice work!!
"Dug"

 

[Trevor Jessie]

Stock pedestals?

Why did you retain the springs instead of going with solid spacers?

 

[Hairyone]

They do look well cool, just need a transparent rocker cover to show them off.
1st Q why? are ratio roller arms not available?
2 have you any pics before assembly
3 how have you held the roller in.

I am glad that there are people out there across the pond with great love for these cars, who are designing & improving bits.
Excellent work
Adrian

 

[Dadandson]

The material is 6061-T6 Aluminum. The rollers are hardened O-1 to 58-62 Rc. The stock pedestals seemed to work fine and David Vizard prefers springs to solid so there is absolutely no lateral movement. The roller is held in with a press fit cross pin. The bushing on the rocker shaft is a material called "Oilight Manganese Bronze". These are preferred over needle rollers because needles will fail eventually and that would cause catastrophic failure.
My whole goal was to design rocker arms that could be installed by a novice, that requires no machining or modifications of OEM parts (the rocker shaft would almost always need to be replaced) and improve performance. I am going to put a few miles on the car and tear the rocker train back apart and see how they look. If they are holding up, and I have the utmost confidence they will, I will make a few more sets and put them on eBay and see what happens. BTW, my target price is under $200 a set.

 

[Whitephrog]

Tim

You will likely have a ready market waiting on you.

 

[jhorton3]

Tim-I'm very impressed! They look great. What cam are you running in your engine and what's the rev limit with these over stock units? If you've got a dyno shop somewhere around you might want to put stock back on, test, then put your new ones on to see what running differences there are between the two.

 

[Dadandson]

I have a stock cam, at least I have not changed it. I am reluctant to put the car on a dyno as I have seen motors blow on them. It is still the same tired short block that was in the car when I bought it. I have to rebuild the rear axle, gear lube leaking, then I am going to build a short block. After that I will go to a dyno. I have been working on this rocker arm/head project for the last 4 months off and on, I still have a business to run, so it make take quite a few months before I can say exactly what the benefits of these arms are. I will keep everyone updated and again this project would not have gone as it has without the direct and indirect help from everyone on this forum. This will be a success for all of us. Thanks again.

 

[Trevor Jessie]

In a nutshell, what did you change on the geometry to get more lift? This is an important question because (and someone correct me if I'm wrong) some high lift cams may cause the angle of the pushrod to be great enough to rub the head depending on the rocker geometry.

 

[blkcorvair]

Tim

You will likely have a ready market waiting on you.

Agreed.

Are you hiding them under a stock valve cover? or alloy neccasary for clearance?

 

[Dadandson]

By changing the dimensions of the fulcrum center, rocker shaft, to the roller and adjusting screw more or less lift can be created. The lift on a stock cam is .270" and the stock dimension of the fulcrum center to the valve center is fixed. So using a CAD, computer aided drafting, I was able to position the centerlines to obtain more "Lift". I was very careful to insure that the push rods would not rub on the head openings. This setup will fit under both stock or alloy covers. There is actually less room under an alloy cover as the side walls are tapered and the stock cover walls are straight. Again, my goal was to design rocker arms that increase performance and could be installed without removing the head or making any other changes to the OEM equipment. Even the adjusting screws on the arms are OEM. That's why I was asking in a previous post where I could get a 9/32-26 BSFT tap.

Correction: The alloy covers have more room vertically but the OEM covers have more room width wise.

 

[Trevor Jessie]

So... you only shortened the distance from fulcrum (rocker shaft center) to the adjustment screw center. Correct?

 

[Dadandson]

I adjusted both as the roller moves from one side of the valve stem to the other. By only moving the adjusting screw an interference issue with the head may arise. Vizard says you can elongate the holes in the rocker towers and achieve what you describe with OEM arms.

 

[Trevor Jessie]

So when the valve is closed the roller is actually is to the side of the valve stem? Here is what a mean (exaggerated for effect)

 

[Dadandson]

Correct. I split the .281" dia of the valve and it is on one side when closed and the other side when open. It is as central as possible.

 

[Trevor Jessie]

OK... I think there is an issue there that needs to be addressed. But I'll leave it for an engineer. (I'm a scientist).

 

[bthompson]

<span style="color: #FF0000"><span style="font-size: 14pt"><span style="font-weight: bold">WOW! </span></span> </span> :thumbsup:

Shiny.