Quote:
Originally Posted by steve99
@ thambu19 how much PI is needed and where load rpm wise to maintain intake valve cleaning properties ?
another question, if you have a look at the intake cam tables at low load rpm they do a weird dance go from zero then negitive then back to zero then increase above zero. I have assumed the negitive dance was emmissions related ? |
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steve99
Are the negative values real? I mean does the the cam actually go there? I thought the rage of authority was only from 0-40deg for intake.
In that case the negative values could be a strategy to force the cams to go to their end-stop or lock-pin positions where Duty cycle = 0. Next time you log data in that area can you check if the DC goes to 0 at this region? This will be a strategy to learn end-stop location so that the ECU can learn the shift in position if any due to tolerance limitations part to part or even chain stretch when it happens on a newer engine. I see that exhaust does not use it. Not sure why not.