M-IKE19
Member
Registered: 25th Nov 07
Location: highlands Drives; Astra GSi Turbo and Corsa GSi
User status: Offline
|
just fitted a bar boost gauge and psi boost gauge i my astra and when the car idles the bar sits at -0.5 bar and the other sits at -20 psi, when i rev it they both go to 0. does anyone no what might cause this??? cheers
|
Nic Barnes
Member
Registered: 5th Apr 04
Location: nowhere near ginger people
User status: Offline
|
thats what is supposed to happen.
|
M-IKE19
Member
Registered: 25th Nov 07
Location: highlands Drives; Astra GSi Turbo and Corsa GSi
User status: Offline
|
no, sorry if im being daft, thought that it was ment to sit at 0 bar on idle then go up to 1 bar or somthing and with the psi one sit at 0 on idle and go to 10 psi etc
|
Nic Barnes
Member
Registered: 5th Apr 04
Location: nowhere near ginger people
User status: Offline
|
you wont get boost unless you load the engine. should be in vacuum on idle and when driving light load. 0 when you rev it not driving then go into boost under heavy load etc
|
Kurt
Member
Registered: 23rd Oct 05
Location: Hi
User status: Offline
|
at idle theres a vacuum isnt there? not boost?
So was my pre deletion right Nic?
[Edited on 18-01-2010 by Kurt]
|
M-IKE19
Member
Registered: 25th Nov 07
Location: highlands Drives; Astra GSi Turbo and Corsa GSi
User status: Offline
|
can you not go into boost just revving it sitting still? new to this turbo stuff lol
|
Kurt
Member
Registered: 23rd Oct 05
Location: Hi
User status: Offline
|
From what i understand, a turbo only works under load. i.e in gear driving down the road
From Wikipedia
Boost threshold
Turbochargers start producing boost only above a certain exhaust mass flow rate (depending on the size of the turbo) which is determined by the engine displacement, rpm, and throttle opening. Without an appropriate exhaust gas flow, they logically cannot force air into the engine. The point at full throttle in which the mass flow in the exhaust is strong enough to force air into the engine is known as the boost threshold rpm. Engineers have, in some cases, been able to reduce the boost threshold rpm to idle speed to allow for instant response. Both Lag and Threshold characteristics can be acquired through the use of a compressor map and a mathematical equation.
[Edited on 18-01-2010 by Kurt]
|
Nic Barnes
Member
Registered: 5th Apr 04
Location: nowhere near ginger people
User status: Offline
|
nah it wont. dump valve might still sound but it should be displaying 0 on gauge.
|
M-IKE19
Member
Registered: 25th Nov 07
Location: highlands Drives; Astra GSi Turbo and Corsa GSi
User status: Offline
|
oh right lol i will go and give that ago, cheers for the help
|
Jake
Member
Registered: 24th Jan 05
User status: Offline
|
no worries mate
|
M-IKE19
Member
Registered: 25th Nov 07
Location: highlands Drives; Astra GSi Turbo and Corsa GSi
User status: Offline
|
all sorted it works lol
|