I understand why and how the HP and TQ are supposed to cross at 5252 rpm.
WHAT IF IT DOESNT??
How Inacurate is it if it crosses at say....? 4200...?
Will it put down a lower number if it crosses at 5252 rpm or a higher number??

Thanks for any help.
Kris

 

facepalm

 

A better way to think of it is this: at 5252RPM HP and Tq are equal. Always.

Here is how you figure them out: HP = Tq * RPM /5252

The reason HP and Tq don't always cross on graphs is the scales can be set up differently. By 'scale' I mean the range of values on the side of the graph that represent Tq and HP. Check out the graph in this recent thread as an example:
https://ls1tech.com/forums/dynamomet...-cam-dyno.html

The Tq scale on the right goes up to 450. But the HP scale on the left goes up to 500. So HP and Tq don't cross at 5252 in this case. If the dyno operator changed the settings on the print out so the Tq and HP scales were the same they would cross.

No matter how you plot the data on a graph this part is the same: at 5252RPM HP and Tq are equal.

 

^What he said.

 

Wow, sweet info. Never knew that, thanks!