boost confusion

[T2Andy]

My boost gauge shows no more than 20psi usually about 18psi but my RR graph
shows a peak of 1.68bar trailing to 1,47bar which converts to 25psi to 21psi ,
question is ,is my guage wrong or the RR results ,when the car was just chipped and modded wg\spring it read the same psi on the gauge that set up couldnt do
25 psi surely .

[Tonks4x4]

How did the RR get its info? Is that what the ecu said it was boosting? If so I would be inclined to trust you mechanical gauge. maybe those map sensors are not quite in tolerance?

[T2Andy]

mmm confusing ,not sure where it was taken from ..

[Tonks4x4]

were they monitoring the car with the laptop through the diag plugs?

[T2Andy]

dont know as we couldnt see from where we were .

[A80Avant]

on the RR they plugged in one of the vaccum hoses that goes to the inlet manifold

Andy, if you recall after the RR we unsrewed your wastegate spring a bit.That may be a reason why you are seing slightly lower boost now.

did it cure the cut though?

[Tonks4x4]

He is still getting boost cut.... ???

[GazzaG60]

must say ive alsways if at all seen lower boost on the rollers than on the road.

Andy if you are getting boost cut and the few the little issues that there seem to be may be cured with a good tune. do you have an af graph?

[T2Andy]

yes its on the dyno sheet mate

[Greg_S]

Yeah mine was a couple of PSI lower than I expected too. On a side note, just logged on after my hol to 5115 new posts!!

[newsh]

Check for leaks where the boost line connects to the ECU and the T piece for the gauge.

Does seem like the dyno pressure might be wrong though.. Have you posted the graph?

Re the boost cutout, have you tried the MAF connector wiggle.

[T2Andy]

Boost cut has gone now after changing to standard spring with a little preload ,but i have found a 1in split in the t\b hose after returning from ADI

[s2_bo]

Ahh classic, i had that on my RS2, once its replaced it like having a new car