If/When you install roller rockers, be aware that on valves that do not have
stellite tips, you may end up with severe concave wear on the top of the
valve stem.
This can lead to excessive valve guide wear or even broken valves. I have
had the
former (1/16th" concavity at the valve tip which put severe side loads on
valves
and guides - cured by grind the valve tip and getting stellite tips).
Another racer
had the later last week at Mt Panorama with resulting severe damage to
engine.
Most valves stem tips are too soft for the hardened pins in the roller
rockers. So,
after you have run the roller rockers for 500 or 1000 miles, loosen the
tappets
well off and inspect the valve tip. This will indicate if you have an
immediate problem.
I'd also be inspecting every few thousand miles.
Note that on non-roller rockers, the sliding action of the rocker causes
relatively even
wear across the tip.
Mike
----- Original Message -----
From: Chuck Ciaffone <chuckc@attglobal.net>
To: spridget list <spridgets@autox.team.net>
Sent: Monday, 11 October 1999 23:59
Subject: Installing Roller Rockers
> Hey Gang,
>
> Just now installing a set of "hi lift" roller rockers I got when I
> visited Min-Mania a week or so ago. The instructions say to gap
> the rockers at 3 thou over standard. I've set the gap at .0016
> and man are those little guyz noisy. Gonna try to cut 'em back
> to .0015 today, but I wonder:
>
> Are roller rockers by nature more noisy?
>
> Sounds more like a '55 Ford 272 mill in there.
>
> chuck
>
>
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