How much boost are you running?
I know people are not holding more than 20psi after 7k...i redline at 7800 and it always drops to 18-19psi... 3500 -6500 rpM I get 26 spike and hold 24 then slightly drops to 22 then at 7K+ it's 18-19psi.
I can hold 22psi to 8000rpms on pump gas. No spike, just a flat 22psi from ~3800-8000rpms.



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