Slow oil pressure gauge

[demott930]

When I start my truck. The oil pressure gauge is delayed. As soon as it goes up the turbo spools. I have a 5" exhaust turbo back. Never did this before putting it on. Also it seems like when I start it it's has a slow start up.

[JumpinJack]

Under normal conditions my gauge wont show any pressure until it fires up and/or under a long crank. I wouldn't think just changing the exhaust would delay oil pressure I switched to a 4" straight pipe and had no diff other than I could hear when the turbo started to spool.