90Rexx

In first and second gear only my boost presure goes right up to 15lbs where my boost cut is set at, every other gear it stays down at 10-11 with no creep. Any ideas what could cause this? im hitting boost cut in the first two gears every pull

I'm using s300 (without boost by gear), blox mbc, gt30r topmount with a tial 38mm gate

Hybrid96EK

Too small of line going to the BC? Poor vac/boost source?

90Rexx

found it to be actually a small machined hole in one of the fittings on the boost controller.... i dont understand why it was there, but it was leaking boost.

wilham320

iTrader: (1)

that hole is supposed to be there... the blox mbc is a knock off of the hallman.

According to Marc Hallman: "The hole is a pressure relief that allows the wastegate to close between shifts. If it was not there the valve would close between shifts and trap the pressure between the wastegate and the valve thus holding the wastegate open. This would make the car very laggy between shifts without it."

From hallman instructions:
"The barb on the Hallman boost controller that connects to the wastegate actuator will have a small hole drilled into it. It is important to leave this hole open, and never switch the wastegate barb and the boost barb."

90Rexx

i jb welded the hole.... problem solved.


blox sucks. that idea is bullshit. as soon as the pressure gets by the ball in the boost controller it leaks out of the hole and makes my boost reference to my wastegate incorrect. id rather have a laggy shift and a safer wastegate boost reference.