when i am at wot and my tranny shifts i get valve clatter,for about 2 or 3 sec. after shift. could this be caused by timing chain or what? i have about 155,000 miles on my tpi 350 powered "Z". i keep all my fluids changed and regular maintenance up to par.any advice on what i can do or check is greatly appreciated.
thanks
john

 

What happens to the oil presure gauge when the shift occurs?

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Later,
Vader
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If you want to beat the World, it might reach up and pull you down...
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it stays above 60+ psi at all times at wot and drops to 45-50 psi at idle

 

John,

You might be getting some lifters pumping up at higher RPM, then suddenly running out of oil at peak (shift point), so that when the RPMs drop, the lifters stop floating and the lash is again evident.

Just a theory, but if the valve lash is set correctly, it almost has to have something to do with lifters starving and collapsing. This is a major reason I like to adjust my valve lash on the lighter side of the specification - 1/2 turn instead of 1 turn after the zero lash point. Those extra few thousandths (actually, more like 20 thou) are just that much farther the lifters can pump up and float the valves.

------------------
Later,
Vader
------------------
If you want to beat the World, it might reach up and pull you down...
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