Loosing boost

[LeeSmith]

Since getting my turbo timer with a boost gauge built in i have been looking at my boost levels quite a lot.

I have noticed that i loose boost at 4500RPM.....I got a feeling it's the turbo.....it's set up to run at 1.0bar so it's not maxed out.

 

[Shaun]

What boost controller are you using :?: Has it been set up properly :?: As this symtom could be whats called 'Hunching' where the boost reach's the desired boost level and then falls off :!:

 

[LeeSmith]

done via bleed valve, a big chunky one

it was done when i bought the car, seemed to run ok so i never bothered getting a boost controller & when it was at powerstation they said it held boost fine.....but the power dropped off later on in the rev range....they said they didn't know what it was! nice of 'em to help...