LS1 lifter and cam distress

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Dan Timberlake
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LS1 lifter and cam distress

Post by Dan Timberlake »

A colleague bought a used GTO LSI several years back to install in his MAzda. INstalled as-was.

After about 20,000 happy miles, valve train noise seemed to be rapidly increasing.
A top end investigation revealed all the rollers still turning freely.
Beehive springs of unknown origin, and Pushrods etched with "Texas speed" or something similar were found installed.

Most of the rollers show varying degrees of distress, from heavy discoloration to deep uniform wear, and severe spalling.
Similarly, the cam lobes's condition ranges from heavy discoloration to deep uniform wear, and severe spalling.

Supposedly the plastic ( OEM?) lifter guide trays are not the "bad" ones with angled flats, based on Internet casting mark lore.

Questions about installed spring height and pressure, closeness to coil bind, cam part number and specs, how the cam was installed, and etc are probably lost to history at this point.

Any comments about possible factors that lead to the sorry condition of the cam and lifters would be appreciated.

thanks,

Dan T
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