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smoker limit

Diesel Tuning Fundamentals

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Discussion and questions related to the course Diesel Tuning Fundamentals

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smoke limit - is the purpose of the smoke limit purely for emissions standards? or is setting its parameters out of range so it never works unhealthy for the engines preformance?

Bit of both. I think it's the simplest way to account for a LOT of variables. There could be a myriad of reasons why there is insufficient air available for the torque (and therefore fuel) requested at any given time.

17.5:1 or higher = Clean

16.0-17.5 = cleanish but borderline on emissions

14.5-16.0:1 = Greying pipe but still making more power. Will not pass emissions

15:1 or lower (removed smoke control)= Needlessly dirty, spools slower and basically gives diesel a bad name without getting you any more power

My take on it,


The Smoke Limit table example in the course (Colorado I think) can you explain the numbers in table, are they a lambda value ie. 0.95 which is very rich or is it a multiplyer or %?

So to edit this table to not limit fuel do you lower the 0.95 or increase it?

Probably in Lambda, lower number = richer or dirtier...

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