Reply to "Dyno Numbers"

As your engine horsepower increases so will the power lost through the system.
The use of a percentage is fairly accurate & 22% would not be far off the mark.
Some cars lose more through the drive-train & other designs less.
A front engine rear wheel drive car will lose more through the drive-train due to the extra components such as the propeller shaft, (which the Pantera obviously does not have).
So working on a 500hp engine with a 22% loss you end up with 390hp at the wheels, a 110hp loss.
If you had a 600 hp motor you would end up with around 468 hp at the wheels, a 132hp loss.
The reason why more power is lost as the engines power is increased is due to friction.
A transmission will not have a set amount of frictional losses.
Loss increases as the horsepower transmitted through the transmission increases.
Imagine two gears meshing within the transmission.
One tooth is pushing against the other tooth.
As the power increases so does the load between those teeth.
More force is being applied.
Friction increases & more power is lost as heat.
(Hence the need for a transmission oil pump & cooler for high horsepower engines).
This also goes for the transmission bearings, drive shafts, upright bearings & tyres, they all see load & frictional losses.
Also remember that you are NOT producing all of your engines power if you are breaking traction & your tyres are spinning.
The engine has to be under load to produce its power & torque.
Hence the dyno to tune the engine under loaded conditions.
So as you increase the engines power all of the driveline components will be under more stress & as long as the driveline holds together the limiting factor will generally be your tyres.
Obviously you will find with more power you start to lose traction, so you fit wider & stickier tyres.
And because of this, you again lose power through the driveline because of the increased traction.
Efficiency & power lost in the drive-line is also about the components used.
CV’s are more efficient than Uni’s.
Certain types of bearings have less parasitic losses than other bearing designs as well as the type of oil being used.

regards,
Tony