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Attached are the results of a stock CPL 858. I hope this helps with some of the discussion.
 

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What happened to the data on the average of runs 242526? Or did I somehow miss that.
 

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What kind of boost # did you have?
 

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Dyno vs. real world

Has anyone done a dyno like this and then compared it with a dyno after the engine was put back in a vehicle?

Edited 03/13/07: I did my vehicle dyno with the injection turned up. This can be seen in the "realistic power" postings here.
 

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newbie here!! great stuff

wow this is exaclty what i've been looking for great stuff!!! you got the numbers just tuning up the stock pump?? a may have missed the details any anything else; timing adjustments??? i know with cat motors the more you turn up the fuel the more advanced the timing gets because the pressure overpowers the injector springs and the injector winds up open longer i know the cummins pump/injectors are different... and i'm unfamiliar with them actually i wouldn't know where to start confused
 

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Some great results there.

I noticed the AFR stays relatively constant. Is that a coincidence of more fuel spinning the turbo faster and keeping things balanced, or was it actively managed?
 

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there is really no AFR in a diesel. power is depends on how much fuel and air can be compressed in the chamber, even though there is a rich and a lean condition. diesel is not affected much because it has different properties from gas.
 

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there is really no AFR in a diesel. power is depends on how much fuel and air can be compressed in the chamber, even though there is a rich and a lean condition. diesel is not affected much because it has different properties from gas.
Yes I realise this. But many dynos (and electronically controlled diesels) do still measure and record the AFR for diagnostics reasons.

Apparently a diesel AFR of 16 is the smoke limit for a common rail type diesel with very high injection pressurses. So around 20 would make sense for a factory diesel running at full load. But I'm interested that it didn't change much with more fuel and boost.
 

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What you need now is a diagram showing the location of the: Fuel Screw, Star Wheel, Smoke Screw,Timing adjustment and cone Position adjustment.

Great work!
 

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THANKS brut67!!!

This is primo stuff, showing bone stock 4BT power & torque and then progressive free tweaks! Glad it was 4BT and not BTA as mine isn't aftercooled yet. Really a great help for dial-in. Thanks MUCH!

JimmieD
 
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