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2000ssnb
October 25th, 2005, 12:21 PM
I find the gram/cyl scale for the spark tables not very
intuitive. I worked for a long time with lb/min.

Is this conversion right:

40lb/min of air at 6000rpm -> 3000engine fillings with air

40 x 450 g = 18000g / min

for one revolution -> 18000/3000 = 6 grams for all cylinders

so 6 grams /8 = 0.75grams/cyl when the MAF sees 40lb/min at 6000rpm.

Gert

bink
October 25th, 2005, 02:40 PM
I find the gram/cyl scale for the spark tables not very
intuitive. I worked for a long time with lb/min.

Is this conversion right:

40lb/min of air at 6000rpm -> 3000engine fillings with air

40 x 450 g = 18000g / min

for one revolution -> 18000/3000 = 6 grams for all cylinders

so 6 grams /8 = 0.75grams/cyl when the MAF sees 40lb/min at 6000rpm.

Gert

Yes. Good work!


Here's the formula most of us use (which you've derived :D) -> g/cyl = [ MAF (g/sec) * 15] / RPM


1 lb = 453.59 grams

40 lb/min = 302.39 grams/sec

g/cyl = [ MAF (g/sec) * 15] / RPM

302.39 * 15 / 6000 = 0.76 (.7560)

Cheers,
joel