Horsepower Calculator

Check it out! Enter vehicle weight, E.T. and trap speed and get your estimated horsepower..

Last night - Car Weight=4550, ET=14.433. Trap Speed = 95.84

Estimated rear wheel horsepower = 305.9

Approx Engine Horsepower 382.4

 

what is ET and speed trap?

 

ET – elapsed time to run from start to finish.

Speed trap - Timing sensors under the track surface that detect cars passing over them. To approximate maximum speed, the distance between a set of sensors is measured as a car passes over them at the end of the track.

 

ok i was going to use this for my truck but basically id have to make a run at the track in order to find everything out? i already know what my truck dynoes in at i just thought id see how accurate this thing was.

 

Good basic rule of thumb I'll grant you, but factor in reaction time at the line, engine temperature, fuel octane level, transmission loss ratio of torque to drive, traction conditions, ABS adjustments to performance, air temperature, humidity & altitude.

Hmmm.. well mebbe not quite as accurate a calculation as we might like.

 

Try it before you diss it. I thought that 382.4 was a very reasonable number for 350hp motor with a superchip.

You are correct, it does not account for altitude, engine temp, blah, blah blah. It eliminates them from the equation. What is measured (fairly accurately) is the power you can put to the ground. The major shortcoming is the aerodynamic drag of the car is not considered, and it is quite a factor at 100mph.

You should see the times I could get if I had put 3500lbs, a more Mustang like weight. That would have put me in the 12's....

Your results may vary....

 

IXLR8,

Computer calculating HP from plugging in numbers is fun... but rarely accurate. I have seen many programs over the years, however, one important element they need built into them is volumetric efficiency. This is where the engine's efficiency is rated -- and never, is it 100%.
IF the programmers put in 80%, or so, that would be for a new or newly rebuilt engine running just about peak effiency, that would be fine, but again, every engine is different, even from the same builder with another similar engine.

I am NOT dissing your calculator. I think it is fun. But it shouldn't be taken as gospel.



MN