V8 rocker shaft bronze bushes

Makes the Yella tera look a bargain...

Yes indeed! They need to either employ or engage a professional engineer (either mechanical, aeronautical, or structural) to design them. Once you know the imposed loads, which is usually the hard part, you can start to configure the component. The rockers will be subjected to normal stress, shear stress, moments, and cyclic loading. Parameters required before you can use FEA (finite element analysis) include material density, Young's Modulus, yield stress, ultimate tensile stress, Poisson ratio, second moment of area if modelling in 2D. They sound pretty impressive that's for sure!

Ron.
 
Hi everyone.

Sorry for the gap since last posting. Progress however has been made. First up was finishing the 16 bronze bushes. Oh and yes I know there are only 15 here. 16 just messed up the phone of the lovely shiny bits.
 

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Next was to press them in to the reamed out rockers. There is 10 microns interference which proved to be exactly the amount required. Had to be careful to align the oil hole which is slightly oversize in the bush to allow for a little misalignment.
 

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First test fit revealed that when pressing the bushes in to the rockers they narrowed by about 6 microns so a few minutes on the honing machine brought them back to having 10 microns clearance. Next time with will be compensated for in the machining stage. Now they fit over the shafts beautifully.
 
Next job is to machine the pedestals. I have decided to go with the option of making pedestals from scratch rather than reaming and sleeving the originals. I think this is a better and more efficient way.
 
Pedestals made. This weekend should see construction and fitment with luck.
 

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Very nice, are you going to offer them to the market?

I have made the tooling to be reused so yes my intention is to offer them once I have proved the concept. My fear is the cost may put people off but I haven’t worked it out yet. I would love to make some more sets for I really have rather enjoyed myself and the tooling is sat there ready to use again.
 
Constructed the rockers today after making some acetyl plugs for the ends. The engine is having new valve stems so might be a little delay before fitment and test.
 

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Heads are back and refitted. Rockers now in place and adjustable pushrods set with the correct preload. I’ve relocated the coil so awaiting a longer lead, then it’ll be for the first start without the splash guards so I can have a good look.
 

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Hi all,

Been really lazy posting the results on the forum. My main reaction to these rockers is ‘WOW!!!!!’. I already had adjustable push rods on the engine so redid all the preloads etc and on starting it up I simply cannot believe the difference. The rocker gear is so quiet, all the mechanical ticking which these engines are known for if they have any degree of rocker wear, or poor quality parts is TOTALLY gone. The engine purrs at idle and when going up the revs sounds so smooth. I’m pretty astounded at the difference. Oil delivery to the rocker is good, it drips nicely from each rocker. After 1000 miles there is no visible wear when I dismantled.

What a modification!! I wish I have some more engines to do it to.
 
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