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Old 13-09-2020, 09:39 PM
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Scott.T Scott.T is offline
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Join Date: Sep 2008
Location: Hastings, East Sussex
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Quote:
Originally Posted by viper1982 View Post
I have a question, in the case that I set a ridiculously high waste gate duty cycle value, but at the same time, I do not modify the corresponding table of boost target. What's going on? How does the ecu handle this situation?

I know that if a very low wgdt value is placed, only the desired momentum is not reached, but in the reverse situation?
You will get oscillating boost as it over achieved and tries to get it under control.
This is quite common for a dyno tuned car using 3rd gear only.
On the drive home the owner gives it 3/4 throttle on the motorway in 5th at 3500rpm. The turbo over achieves and oscillates or in some cases hits the fuel cut limit.

When road tuning, use 3rd for the bulk of it but then try a 4th or 5th from 2500rpm to about 4500rpm to check for overshoot.
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