Quote:
Originally Posted by Element Tuning
Be careful here as there was a complete redesign I believe to help with the rocker ejection that included longer valve stems, different rockers, and different pivots. I believe that was in an effort to change the rocker angle and to provide adequate oil volume to the pivot in an effort to reduce the rockers ejecting. It does appear the newer FA motors don't seem to have a consistent rocker ejection issue.
Our engine packages boost oil pressure by 20+ psi so we just aren't seeing the rockers eject on these older FA20s but I suspect "volume" to the pivot helps. On the new engines with the redesigned pivots there's no change in overall oil pressure unfortunately from what we've seen. I suspect this is the same for most as people are still sending us engines with spun rod bearings on the BRZ and also the WRX FA20DIT.
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The new pivot has a smaller hole which would reduce "volume". My theory is the pivot actually works as a hydraulic lifter and a smaller hole would increase the lift and in theory reduce the slop in the rocker. I just ordered a single pivot so I can get it in my hand and do some measurements.
Sad to hear the newer engines still have oiling issues. I suspected the main reason you're primarily seeing 2013's failing was simply due to the age/miles. This time next year we will probably have a weekly thread on spun bearings on a 2014 like we do with the 2013 lately. Spun bearings on a 2013 with 80K miles on a fully stock car and proper oil levels is unreasonable IMO. I don't care how hard it's driven.