Racepak CC's per Turn

On the racepak software when you have a flow meter you also get a graph for cc's per turn. I am curious what this is a measure of and how/if anyone uses it to check for problems or tuning aids. I am just not that familiar with cc's per turn. Anyone explanations would be appreciated. Thanks,
Eric

 

CC's per turn. This is a relationship between the fuel flow meter numbers compared to engine RPM calculated internally by the program.

CC's are a measurement. Cubic centimeters.

Per turn is one crankshaft revolution.

If the CC's per turn number was 10, that means each time the crankshaft made one full turn the fuel system produced 10 CC's of fuel through the fuel system as measured by your flow meter.

CC's per turn is used to track your fuel curve and to determine how linear your system is.

 

Randy,
Thanks for the explanation, greatly appreciated!

Eric

 

What do you mean by linear? Like if the line has any abrupt changes, you have an issue somewhere?

 

CC Per Turn is a way to check and see when a bypass opens and also to zero your graph (or another way to do so). Remember when looking at CC's Per Turn in reference to time (secs.) on the graph that "NHRA Time" is not going to be the same as the graph, there's a small difference.

Brandon Booher
NHRA TAD #34

 

Depends on where you set your zero seconds start time. Some start it at the fuel pressure change, some at the first tick of driveshaft, some have their own method that can match the time slip conclusively.

 

Randy is spot-on correct, this isn't his first rodeo

Brandon Booher
NHRA TAD #34