I have a turbosmart manual boost controller that I set at 19 psi that will hold at 19 for the most part;however, when i start out in first and go full throttle up thru first and second gears it will spike at 21 and fall back and go back and forth between 16 and 17 psi. When I am cruising in fourth or fifth gear and I press full throttle it will go to 20-21 psi. This morning after the car warmed up to operating temperature I pulled out onto the highway and it would go as high as 23-24 psi! Anyone heard of this before? Would an electronic boost conroller be better for holding a steady boost pressure, and if so, which one do you recommend? Any help would be greatly appreciated!!

 

Check if the knob didn't manage to turn itself. My MBC did sort of the same thing, but I tightened the nut to lock it in and it stays at 20psi all the way and not 1psi drop.

FYI - I have a Joe P MBC.