Hi All, I was talking to a friend who is into racing/sprints etc he was saying that the result form a rolling road the BHP and Torque figure should cross at 5250RPM it the RR is setup correctly. Have a look at your print outs and see if this is correct.

 

also should the Rolling Road take in to account the weight of the car for the correct loading to be applied?

 

Yes he's correct, I'd also heard that, and all my RR printout's cross at 5250.

 

any more?

 

The two curves will cross at 5250 Rpm only if the power is shown in BHP and the torque is in Lb/Ft, and they are shown on the same scale.
That's all. It doesn't mean the rolling road is set up right.

 

ok, so if it is set to read in bhp and lbft it should cross at 5250rpm?

 

Only if both bhp and Ib ft are the same scale as normski said.

 

yes.

The reason is a rolling road measures Torque and then calculated BHP.

BHP = (torque x rpm) / 5252

Hence the cross at 5252rpm.

Alex

 

thats great thanks