You can run up to 20ish on stock valve springs before you see valve float. Won't matter on stock fuel and stockvturbo. Anything over 14psi on stock turbo is just a heat pump. Stock fuel won't get you more than 160hp.

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1995 E420 Schwarz
1995 E300 Weiss
#1987 300D Sturmmachine
#1991 300D Nearly Perfect
#1994 E320 Cabriolet
#1995 E320 Touring
#1985 300D Sedan
OBK #42