Shortened version of a long story.
When I had the P3.5 put on the GSi I put it on the rollers which showed up a rather major issue as you will see from the unsightly power curve below:
After a few discussions with MPG and some testing I found that the fuel pressure at the rail was miles away from where it should have been, infact it was around 2bar lower than it should have been at only 2.8bar of pressure.
A new FSE high flow pump was fitted but it appeared to be the same. That accompanied with a new pressure regulator & pump relay.
With time being an issue before going to the ring there wasnt a lot could be done bar take the car easy whils it was at the Ring (still managed a 10min 13second lap taking it easy on low boost). However there was an additional issue where by on some of the longer up hill sections under full load the car was backing boost right off for a split second and then coming back so obviously something else wasnt right.
She made it back no problems however and on the way back from was dropped back in at MPG for further diagnosis. Once there it was found that the fuel pump was still an issue which was then replaced by a Regal high flow unit and hey-presto pressures back where it should be.
The boost problem was found to be a pin hol in on of the boost hoses coming off the intercooler. So all sorted she was picked back up again on Wednesday night and went back on the rollers again yesterday morning, much improved:
Power figures are a little low really given its an LEH on P3.5 at 275bhp but the main concern is that the car is now running 100% and after a short run last night of 130miles with Coo, Ally & Turbodave and am very happy with how the car drives, fulll chat in 2nd and 3rd gear is awesome. Just need to get some big brakes on there bow