John,
>Neil, whatever the cam lift, you should not change the pushrod length.
John
Can you explain in more detail as to why not? The two _blueprinting_ books
(not motor rebuild books) I have both mention this as being an essential
adjustment, when a motor has been modified in certain ways - to ensure the
correct operating geometry of the rockers. They recommend various methods of
adjusting the pushrods (not talking about LBC's) which I have actually
already discussed on this BBS before - I think someone came back with using
tubular pushrods (Bill?) which can be adjusted by machining & heat - (I
think) - and that the stock pushrods are non adjustable. I'm not replacing
with stock pushrods, I just need the length data.
Can someone confirm this for me or am I dreaming again? <G> The net result
of the decking/skimming etc alters the clearance between rocker arm and
pushrod. My assumption is that increasing the clearance at the arm will
resolve the clearance issure, but ultimately the angle of the rocker arm is
affected by this adjustment and will affect the load placed on the rocker
arms, and increase load on the rocker mechanism. If I am to spend the $ to
flowbench the head, I would like to get all this spot on, but more
importantly, as I'm considering roller rockers, I don't want these to take
any more load than they already do. Apparently due to the increased weight,
and different distribution of that weight, r/r's requires the use of
slightly firmer springs to maintain the same valve bounce rpm.This is what I
have read, and am requoting from a few sources. It's an interesting topic.
:)
Cheers,
Neil.
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