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Old 01-09-2006, 10:10 AM   #1
stewy612
Scooby Newbie
 
Member#: 76242
Join Date: Dec 2004
Chapter/Region: South East
Location: Kennesaw, GA
Vehicle:
2007 Spec. B
DGM

Default Unstable Boost?

Hey guys i've got an 02 Stage 2 HWG AP WRX. I don't know why when i hit it, the car spikes to 17 and then to 14 and then to 17 and then to 14 so on and so forth

anybody have any idea why

thanks

-Stewy
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Old 01-09-2006, 10:45 AM   #2
Kha0S
Scooby Guru
 
Member#: 8808
Join Date: Jul 2001
Chapter/Region: NESIC
Location: Grantham, NH
Vehicle:
2011 WRX (DGM 5D)
2002 WRX/2003 SVTF

Default

Try running the normal Stage 2 map versus the HWG map. Boost spiking is a common problem with aftermarket exhaust systems (particularly those with very low backpressure)... my car did it with the factory tune and high-flow exhaust.

The turbo dynamics maps in the ECU need to be adjusted to avoid the spiking, and the tuner usually will manipulate those tables when designing a map. The HWG map uses aggressive wastegate turbo dynamics to achieve the right boost levels in situations where the standard map won't.

As ambient air temps drop, the wastegate bleeder efficiency improves, so, while you might need the HWG map to meet your target boost during the summer, the non-HWG map will probably work fine in lower ambient temperatures. If the standard map can hit the right peak boost number, you shouldn't run the HWG map.
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Old 01-09-2006, 10:59 AM   #3
stewy612
Scooby Newbie
 
Member#: 76242
Join Date: Dec 2004
Chapter/Region: South East
Location: Kennesaw, GA
Vehicle:
2007 Spec. B
DGM

Default

sweet thankyou man for a good reply...i thought that might be a solution

-Stewy
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Old 01-09-2006, 11:03 AM   #4
fatray
Scooby Specialist
 
Member#: 18150
Join Date: Apr 2002
Chapter/Region: MAIC
Location: Baltimore MD
Vehicle:
2002 WRX Wagon EJ207
Velocity Red, Liberal kit

Default

getting rid of the stock BC fixed my unstable boost.
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