I believe the factory MB safety fuel cutoff is actuated at 1.1bar @15psi so setting above that won't do you any good unless you bypass it and that wouldn't be very smart.... I would say 13.5-14psi is a good stopping point since it is clearly within the MB "safety" envelope. If you were willing to do a custom intercooler ala Ben Ridge then boost could easily be tweaked up to 17-18psi LIKELY without issues. It your engine so experiment at your own financial peril. RT

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