<VV> Cam profile WAS noisey cam

[Bryan Blackwell]

Really?  I'm a little surprised given that it (the OT-10) is aimed at  
the low end of the RPM range.  I would expect that since it's a  
hydraulic cam basically for 110 engines it would be quiet.

There is some possibility that it requires custom pushrods, I know  
that Otto Parts suggested checking the geometry in the old catalog.  I  
bring that up because I have been told that if the geometry is off  
enough, it will lead to some noise, although I'm not quite certain of  
the reason why.

Finally, there is the issue that on teardown Tim found evidence of  
wear, even though he used a ZDDP additive.

So, anybody out there successfully run an OT-10 recently?  Was it  
noisy?  What break in procedure and lube was used?  Other comments?

--Bryan

On Dec 1, 2009, at 6:37 AM, kenpepke at juno.com wrote:

> As this operational noise is a common condition with that particular  
> cam it is not so likely the noise is the fault of the engine  
> assembler.  We all know that mechanical / solid lifter cams have a  
> slight ramp at the beginning of the profile to take up the lash ...  
> we hear and expect that slight operational noise at that part of the  
> engine cycle. Some even like it :-)