I was wondering if anybody knows how to take microseconds and rpm and plug them into a spread sheet or something to come up with crank angle degrees of rotation?
Question: Ms And Rpm = Cad
- Thread starter BIG RICHIE
- Start date
I can't find it right now.
IIRC, it's just RPM x 60 / fuelshot(msec) = Degrees of crank rotation.
Let me double check.
IIRC, it's just RPM x 60 / fuelshot(msec) = Degrees of crank rotation.
Let me double check.
THANK YOU VERY MUCH :hail:
I DON'T WANT TO SOUND LIKE A RETARD BUT I DON'T SAVVY( IIRC ):dontknow:
I DON'T WANT TO SOUND LIKE A RETARD BUT I DON'T SAVVY( IIRC ):dontknow:
IF that is correct say 3000 rpm 3100uS shot is 58* of crank rotation and rough halv of that is before TDC with 30* max timing
OK:
You divide RPM by 60 to get RPS - Revs per second. Minutes are useless.
Now you take that number and divide into 1 ( 1 / RPS ) and get Seconds per Rev, or how long it takes the crank to go around in a circle at that RPM in seconds.
Now you take how long the injector is open (in seconds) and divide by the Seconds Per Rev, and it gives you How Much Of A Revolution It Moved. You will need to divide the fuel shot by a million to get seconds.
Times that by 360 to get how many degrees.
You divide RPM by 60 to get RPS - Revs per second. Minutes are useless.
Now you take that number and divide into 1 ( 1 / RPS ) and get Seconds per Rev, or how long it takes the crank to go around in a circle at that RPM in seconds.
Now you take how long the injector is open (in seconds) and divide by the Seconds Per Rev, and it gives you How Much Of A Revolution It Moved. You will need to divide the fuel shot by a million to get seconds.
Times that by 360 to get how many degrees.
RIGHT ON! AGAIN THANK YOU.THAT JUST UNLOCKED A BUNCH OF STUFF FOR ME.
I MADE A SPREAD SHEET USING THE FORMULA (RPM * 6 * FuelShot (ms) / 1,000,000 = degrees) AND CHECKED IT AGAINST AN LLY LOG AND IT WORKED PERFECTLY.
I MADE A SPREAD SHEET USING THE FORMULA (RPM * 6 * FuelShot (ms) / 1,000,000 = degrees) AND CHECKED IT AGAINST AN LLY LOG AND IT WORKED PERFECTLY.
Here is the spread sheet. It is rather large and you might not like my RPM or MS intervals so all you have to do is change what is in the yellow boxes and the degrees will follow. If you just want a quick number use the three boxes in the upper left hand side, same thing, type in your RPM and MS and you will be good to go.:happydance:
My timing calc will do the same thing. Just change the desired % BTDC to 100.
View attachment timingV2(2).zip
View attachment timingV2(2).zip