Things to remember about valve adjustment.
The need to adjust valves is counter intuitive. That is you would think
with wear of the valve train over time would loosen them up. This is not
true, because the majority of wear occurs at the valve seat, making the
clearance at the valve to rocker smaller over time. If not adjusted,
eventually, the valve is staying open slightly at all times, leading to loss
of compression, and burnt exhaust valves. Also, as metal heats up, it
expands, reducing the clearance. Check it out some time. I run a Valve
lash for a cold engine at .014. Bring the engine to full operating
temperature and recheck. The exhaust valve clearance will have shrunk to as
little as .006. (This is why the engine gets quieter as it warms up).
Competition engine clearance should be .002 greater than the stock clearance
because of the higher heat and faster wear encountered by a race engine. But
it is still a case of more is not better, as too much clearance will
accelerate cam lobe and rocker arm wear, and each .001 of clearance more
than necessary is equivalent to a loss of cam lift and duration.
David Riker
63 Falcon
70 Torino
74 Midget
http://home.pacbell.net/davriker/
----- Original Message -----
From "Robert E. Shlafer" <PilotRob at webtv.net>
To: <DLancer7676@cs.com>
Cc: <pythias@pacifier.com>; <spridgets@autox.team.net>
Sent: Friday, December 27, 2002 7:29 PM
Subject: Re: click adjust revisited
> David C. writes:
>
> "It is better to hear them......"
>
> Absolutely, David!
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