Originally Posted by
MADMAXPTT
Try to raise revs with light throttle without boost, if it passes 4000rpm without any problems then it's possible that your fuel pressure regulator doesn't raise fuel pressure when boost comes! (Check it with wideband)
Try another fuel pressure regulator!
Forgot to say this is also new. But will give it try to see if it raises as much as the boost does.
I got an output at the from of the fuelregulator also is this normal you can put a gauge in there if liked same as the uprated aftermarket ones.
Steven