once a head is skimmed, the leading side of the cambelts going to be loosened right, either upping the chances for a belt slip, or knocking out the timing a touch.
is this what a vernier pulley is primarily use for ? ... to take up that slack ?
skimmed heads vs. mechanical timing
once a head is skimmed, the leading side of the cambelts going to be loosened right, either upping the chances for a belt slip, or knocking out the timing a touch.
is this what a vernier pulley is primarily use for ? ... to take up that slack ?
yeah it will do.On my grasser engine my old head head been skimmed 1.5mm and as such the belt in the right timing position was flopping about like a soft nob.
As I couldn't run a vernier pulley (as per class rules) Id have had to run it slightly retarded
I have a new head now
andy, surely you could move the timing peg slightly......it would be impressive for a scrute to find that
this is one of the reasons I am against skimming for the sake of it.Originally Posted by jimbob-mcgrew
unless there is surface damage, then they simply don't need skimming for normal road use.
in something like andy's competition class, skimming is rife to attempt to get some extra compression & thus extra hp, but it then has its downsides, like the timing being out, then the dizzy timing will be out too & the engine will be a sod to get running bang on unless you start 3d mapping or similar
that's why I binned that head.
what dya mean regarding scrutineering?
vernier pulleys not allowed but I could run it timed how I please
i think he means moving the peg behind the pulley to compensate. a custom fix, out of site
pretty sly mo,
it would be tricky to get the peg in the right place, but it would pay with power
A trick bit of machining could easily see this done only retarding a few mm
as for the head skimming in that case can you not run thicker or 2 gaskets not that it matters but just a question
not a fan of skimming I just ask for a pass to check it removing dirt basically
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