BOOST PRESSURE

[A3-BEN]

morning all!

just out of interest, what sort of pressure should i expect from a standard 140pd?
both under load and when revved up in park

cheers

 

[Bigjohn_A3]

I'm getting 20psi of boost under load on my 140cr

 

[Keram]

 

[A3-BEN]

Had it out and it peaks at 1.5 bar. However I'm concerned I may have a boost leak.
When I nail it the boost climbs up to 1.5 and stays there between 1500-3200rpm but then from there to 4500 it drops off to about 1.2bar. Then when it changes up does the same again. Is this due to not been able to make as much pressure at higher rpm or is a sign of a leak

 

[bentwenty]

Had it out and it peaks at 1.5 bar. However I'm concerned I may have a boost leak.
When I nail it the boost climbs up to 1.5 and stays there between 1500-3200rpm but then from there to 4500 it drops off to about 1.2bar. Then when it changes up does the same again. Is this due to not been able to make as much pressure at higher rpm or is a sign of a leak

It should hold that peak until redline.
Higher RPM = more exhaust gas passing through hot side = more boost pressure. There will of course be a greater volume of air going into the intake, but it should still hold peak boost.
Mine (stage one mapped) will hold 1.8 bar from about 1600 until the hard cut at 4300.

 

[57mab57]

MIne is like A3-Ben's. Peaks at 20psi (1.4 bar) up to 3000 and then falls off to 4500 (16psi). (Dash Command data) . Should I be looking for a leak? A3-Ben, did you find one?

 

[Rick @ Unicorn Motor Dev.]

No, it is fine.

Around 1.2 bar at high RPM is correct.

Rick

 

[57mab57]

Rick, Many thanks for your reply - I was beginning to worry!

 

[oliver-audi]

Mines just blew of a intercooler pipe I think might be over boosting do you think this could be right or is it a common problem ?