[Vwdiesel] Cetane and mileage

[HWY9FERGS at cs.com]

New guy  here.  I wanted to correct my statement about varying the stroke of 
the pump when tuning.  It is actually just varying WHEN the pump stroke starts 
(as in timing, duh).  The stroke always stays the same.  Anyway, it seems to 
me when you are running a higher cetane fuel, then it's increased tendancy to 
ignite effectively advances the timing, and is better for efficiency.  So 
stands to reason if you are running crappy low cetane fuel, perhaps advancing the 
pump timing (a little beyond specs) might be called for. The question is-how 
much can you bump up the timing without risking damage and should it even be 
considered?? You could compare it to timing your gas engine by advancing until 
you hear the pinging and then backing off a tad. I know from experience my gas 
engines run stronger and get better mileage when I run the timing more 
advanced.  Anyone ever experiment with running with timing more advanced on their TD? 
Just some food for thought.  Later on, Doug