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Re: Duty Cycle Meter

-- [ From: Huw Powell * EMC.Ver #3.1a ] --

>I can't tell any difference in the ability of the F/V to keep the O2 sensor
at 0.5V with setting >the DC from 40-60%. I have found that with a DC
setting of 42% average (the high portion on >the scope oscillates from 5-7
mSec. 5/14=35%, 7/14=50%, 42% average) there does seem >to be better
throttle response. This is just a seat of the pants observation but it seems
like the >turbo boost pressure comes up earlier at low rpm making for better
throttle response.

>I am not 100% sure when I talk of 42% DC if it is the same as others. When
observed with a >scope I think the high signal (+12V) is when the F/V is
closed and a low (0.0 V) is when the >F/V is open. This 42% number would
then mean that the F/V is closed 42% of the time and >open 58%. I do know
from 50% DC that you have to turn the 3mm screw CCW to go to >42%.

Wow, that's the most precise and concise description imaginable of what I
see when I measure the FV DC.  Impresssive.

The point of the 50% is it is in the middle.  The DC can range from a low to
a high limit (5-95%? help me here?) and by setting it lower at idle, there
is more room for "high" duty cycle operation.  Don't know if this comes into
play while operating without a meter in the car...

hey, now there's an idea.  I'll take one...

Huw Powell


82+(79-97) Audi Coupe (GT) parts is parts...