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Old 04-01-2015, 04:46 PM   #100 (permalink)
ever_green
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Join Date: May 2011
Location: Toronto
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gueff - '19 Mercedes Benz A250 4MATIC AMG
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Quote:
Originally Posted by serialk11r View Post
Well, lean burn is better than cooled EGR like I mentioned for attaining complete combustion. Of course, the biggest problem is getting rid of the NOx, and the current NOx traps are not a good solution.

Since you've experimented with this, do you mind sharing your fueling tables? I'm thinking about getting a BRZ and I'm super excited to fiddle with the ECU (that is, lean burn!). Just to get an idea of how lean you can go at what speed.
Standard Subaru ecu does not allow you to go leaner than 14.68 Afr or lambda 1.0 in closed loop. What you have to do is induce a fulltime open loop behavior and then have the Maf sensor underestimate airflow by reduce Maf scaling. This is a lot of work as it requires you to reduce the engine load scale across the board in ecu or else it will think there is less cylinder pressure than actually is and run too much timing (this is just one example). Also on the BRZ I highly doubt this is feasible. The direct injection and firing angle tables are extremely confusing and I wouldn't dare tinker with it.
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