I could be wrong but no movement is ideal. If you have more than a little...Like you said, contact BNR...
Oh BAC5.2 is pretty good twith this type of thing too...
178,000+ miles, 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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