The Tuners have found a timing flaw that can cause burnt valves.
My machine shop buddy, dose a lot of these heads for the different dealers and repair shops in CT. When I told him about the timing flaw, he said, "oh, that explains it, why see see so many with bad valves.
My 05 has been on Cobb AP since 8000 miles. When he rebuilt my heads this past May, he said mine was the first one of these heads that didn't need any valves of guide work.
My Tuner has also found a the same flaw on the 5th gen's.
BTW, I have had a Perrin panel filter in the wagon since about 3000 miles.
193k, 5/20/12 new ej257 short block, 8/20/11 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. CHECK your oil, these cars use it.
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