Fred,
When ever you have a cam reground or install a new one with
specifications other than stock, you will get new clearance figures.
Those however are only starting points. Set the clearances to the new
specs and drive the car until you know the engine is at operating
temperature. (usually 20 minutes) If the valves are still making noise,
than go back and reduce the clearance. The amount you reduce it by, is
directly related to how loud the noise was. If it was fairly loud, drop
back .004, if it was getting quieter, drop back .002. Do this until
the noise just goes away at operating temps. If you leave the gap to
large and continue to hear the noise, you will most likely peen the end
of the valve in time. If you set the clearance to tight, you risk
burning a valve. As you may know when the engine warms up, engine parts
tend to grow. That is one of the reasons for this gap.
Now before I go any farther I should let it be known that on my car
(TR-6) the valve clearances are the same for the intake and exhaust even
with the new cam specs. Make sure you make your adjustments accordingly
as I am not that familiar with the TR-4 engine. (or dashboards!)
Pat in NC :}
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