Hi, Paul,
> Yesterday, while doing a pre-season check, I discovered that whilst the
gap
> on No. 8 at the classic 'rule of nine' position (No. 1 fully down) was
> correct (15 cold), if I turned the crank a little more the gap went up to
> about 21! This also happened to No. 6 but to a lesser degree, and also to
> No. 7 but this time it was slightly *before* No. 2 was fully down.
Had this myself on my '68 GT. The idea is to get the valve(s) being checked
on the base circle of the cam which should-in theory-be opposite the 'rule
of nine' companion valve. In reality, spotting the 'fully open' position for
that valve is a bit hit and miss.
My solution was to use a dial gauge (on magnetic stand) on the companion
valve to check that it really is on the exact peak of the cam. Sometimes, I
had to 'average' the turning of the crank to get this point spot on.
My hypothesis is that standard B cams must have very long silencing ramps.
Support for this is that the Midget, Triumph Spit and 2.5PI, Ford Essex and
Kent and many other OHV lumps I've set never gave this problem.
Cheers,
Dave Hill
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