HEAT SOAK~~~LOWERS BOOST?!?
07-24-2005, 12:46 PM
#33
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You edited your original post. Now that it's much less vague I can give you a better answer:
You will notice a power reduction because of reduced density and increased IAT's causing the ECU to pull wholesale amounts of timing, but you shouldn't notice a change in the actual boost value, especially with a stock or conservative chip.
If you're running a very aggressive chip like XR or running an MBC/EBC and keeping the compressor at its limit, then you might see a reduction in boost due to the compressor hitting an efficiency wall earlier because of the decreased inlet air density (PR limitation). Otherwise you should see it stay the same or get a bit higher in the ECU's attempt to keep the same torque value with greater boost pressure.
Bottom line: IC's will always help.
Oh, and by the way: Boyles law and Charles law applies to everything above.
If you're running a very aggressive chip like XR or running an MBC/EBC and keeping the compressor at its limit, then you might see a reduction in boost due to the compressor hitting an efficiency wall earlier because of the decreased inlet air density (PR limitation). Otherwise you should see it stay the same or get a bit higher in the ECU's attempt to keep the same torque value with greater boost pressure.
Bottom line: IC's will always help.
Oh, and by the way: Boyles law and Charles law applies to everything above.
07-24-2005, 01:36 PM
#34
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So then there's something wrong with my car?
If you are saying that the IAT only retards the timing but will not lower the actual boost level, then there's something wrong with my car then. I'm running stock ECU and everything else. The only upgrade so far are Hyperboost HX Divertor Valves, since I thought the stock ones broke and was causing the boost drop. My TBB is fine. Don't know where the F-hose is, so haven't check that. No check engine light, no VAG tool to see if anything is wrong, so here I am guessing on heat soak.
I've even heard that the turbo exhaust actuator can go bad and lowers the boost. I'm just lost right now.
I've even heard that the turbo exhaust actuator can go bad and lowers the boost. I'm just lost right now.
07-24-2005, 01:42 PM
#36
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Yep, looks to be so. VAG and pressure test. You could have a leak and throttle cut...
from a deviation. If it's really bad the car will go into limp mode and provide very little boost.
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