Quote:
Originally posted by Wayne at Pelican Parts
Forged = Bad. Porsche designed the later rockers to be "breakable" upon impact to protect the rest of the valvetrain. They found the forged rockers were too strong, and if piston / valve impact occurred, they resulted in bent valves...
Toss the forged ones, and buy new cast ones...
-Wayne
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It is true that Porsche redesigned the later rocker to be breakable but I'm not certain that cost was not a major factor in that equation. Still most if not all early factory racing engines were built with forged rockers. It has been my experience that forged rockers offer better reliability, are lighter and have a slightly better rocker ratio [more valve lift]. Porsche has redesigned their cast rockers for more strength over the years making them ever heavier.
If your concern is survival after valve/ piston impact, perhaps greater valve to piston clearance, ty retainers, Supertec valve springs or a simple rev limiter make better sense.
Racing engines encounter extreme conditions requiring better parts but if the parts are better for racing they are quite often better for every day use.
BTW: If you have valve to piston contact that does not bend the valve you must still replace the valve or risk the probability of the valve breaking during ordinary use.
If you are planning on throwing early forged rockers away please throw them in my direction.
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