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Discussion Starter #1
Main goal was, to achieve the correct mid lift geometry for even motion and speeds plus the benefit of a changed Ratio
So a correct CAD model from the Head AND an verification in real time was absolute needed.

First, i made a measuring tool to set the baselobe circle of camshaft to the valvetip in a relevant distance



And made some measurements.
On a stock, never touched engine


And on a new build one



After this, i could design around these measurement a Roller Rocker



 

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Discussion Starter #2 (Edited)
So it was time to made some Chips :)




Also Stud girdle is needed


As i had a long time a set of V8 Roller Rockers laying around, i used the main Axle and converted it to my needs.
Rolls and Axles at the end were made new.

So it were time for a real time geometry check
 

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Discussion Starter #3
This is the area wich a standard rocker touch on the top of the valve

And this, with my roller rocker

When you look carefully, you see that the mark is slightly of the middle...around 1mm
Now it came to a nice feature i build in it. The flat area on top of the rocker is no accident, it is for measuring the geometry!
When the plane area and the bolt of the rocker are in a 90 degrees situation under half camshaft lift, you achieved the correct midlift geometry

To check this, i made a small tool


As you can see, it was slightly of....so i had to shorten the lifter to achieve the right geometry


The aftermath, a perfect middle and small contact patch on the Valve Stem
 

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Discussion Starter #4
In result, Valvelift on the Valve with normal rocker

And with the roller rocker



Then it was time for some real world testing, my friends high competitive slalom car was a good playground for it.

As these old lump has really some valvetrain geometry issues with normal rockers, it should be gain really something
Here is the Max Valvelift with a original Rocker (Camcard says, 12.3mm lift)

And with the installed rocker


Test seemed to be good, but we had a rockerbolt failure in the third run :(
The bolts where not in perfect shape, the failed bolt lost some of its threads before....but was no time to get in a new one under that circumstances.
Other downside was, the rolls on the lifter side stop turning and get flat spots.
Motivation was not longer there, it was a long time and stressfull project until this happens with many ups and downs so i decided to put it in one corner of my workshop and will come back later to it when the head is free enough for it.
 

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Discussion Starter #5
Someday i had the thought in my mind, that i didn´t know how much the aluminum rocker will withstand.
Sure i made a FEM Analyses from CAD, but this is so depending under the entered circumstances, that i really did not want to hold my hand into fire for that calculation.
So i made a small testjig...



And put it under my shop press!
Aftermath:


At 5ton of force, the holding pin split in half!
Aluminium still intact (besides some deformation from the broken bolt)

To show that little sucker who is the boss in this house, i changed the bolt to a mild steel screw and give it anonther shot... :lmao:

Aluminium still intact, not split in half as i thought :)

But then it comes the next question...when failure the original ones!?!?!?
Time to find out with another jig ;)
 

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Discussion Starter #6
The result was upsetting...it went so fast, that i even not see how much force it was applied until it happens this:

Quite shocked i immolate another original one an was now more carefully with my press.
With 1 ton of force, you could hear the first pinging noise....
With 1.5ton there where the first really small crack
With 2 ton force, a crack occured that under normal circumstances the rocker would be split in half!!!



So this shows, the aluminium rocker body will withstand under that design minimum double the force than a original one!!!

Some months later, i thought that this project have to be finished...so some new parts where made
And the original bodys where another time machined for better lubrication of the rolls





I installed this now to my bone stock C24NE Omega for real time testing in a daily use



These are running now flawless every day on the original hydraulic camshaft...no problems with stopped rolling rolls
The materials for rolls and pins are now really good ones, no wear showed up until today.
Maybe i could make a back to back dyno test with the original rockers, as with the uprated geometry, the original camshaft has now 0.7mm more lift than stock.

The long term plan is, in the next months i will install my 2.5l development engine to this car and will further test it with more RPM. (original c24ne revs only 5500)And then, there is a roller lifter camshaft also laying around ;)

Regards Rene
 
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