poor mans dyno

[DeepRoots]

i can't remember where (one of these forums) had some way to calculate approximate horsepower with just the 0-60 times and weight of the truck.

i was bored between jobsites today (and I got a new watch with stopwatch abilities). 0-60 in 12 seconds is my trucks best... not superfast but it's livable.

 

[tonkadoctor]

The formula is for 0-60 times to BHP is

BHP = lbs of car / 2.2 / time / .9


so lets give it a try my rough 0 - 60 time was between 5 and 6 seconds counting 1000,2000,3000,4000.......Just like the Army taught me in jump school and that's pretty acurate for a short period of time.

8000 lbs / 2.2 / 6 seconds / .9 = 673 BHP
8000 lbs / 2.2 / 5 seconds / .9 = 808 BHP

This formula is so inacurate it isn't funny.......Tells me the PSD in my 8000 lb (yes it's been on a scale) 2000 CC dually is putting out 673 to 808 BHP (BHP is crankshaft HP) .

Can't wait til I get a chip now so I can brag about my 1000 HP PSD when I get my 0-60 mph time down to 4 seconds

Here's one for a 1/4 mile http://www.dsm.org/tools/calchp.htm might be a little more accurate but I have no idea what my 1/4 mile times or speed is.

 

[DeepRoots]

hmmm, i got 245hp.
bit high.... nearly believable
maybe this is how banks does thier calculations on thier webpage

I've never really cared much for braggin on hp or anything... like I said, just bored and curious. Thats interesting tho, thanks alot.

Drew

 

[Mr_Roboto]

The formula is probably intended for run of the mill passenger cars, not high torque low revving diesel trucks.

The high torque engine will accelerate a truck much faster than a 150HP high revving 4 cylinder engine.

 

[tonkadoctor]

I'd say that the formula is prolly better suited to measuring torque that was actually transferred to the ground instead of HP

Too many variables like gearing, tire size, etc.... to measure HP & torque like this......Mabey this is how a buddy of mine figured out he had an 8 second (1/4 mile) Honda Civic His POS was bone stock with an intake and coffee can muffler on it and swore up and down it would run 8 seconds when I called BS on him in front of about 20 other people.

Still was kinda funny to play with the numbers.....Wifey rolled her eyes and said "Ya Right" and walked away laughing

 

[subway]

yea a simple change of gears will make you quicker with the exact same engine. its an amusing estimation though......

i enjoyed eating honda and toyotas with my primer black 82 GT mustang. hhhmmmm i miss that car sometimes but it saves me allot in tickets now that it is gone

 

[rubberfish]

Oddly enough, It worked out with my setup.

 

[yARIC008]

If we compiled alot of 0-60 times and alot of actual horse powers we probably could set up some sort of regression that may be more accurate. If we did that with torques and times as well and set up some system of simultaneous equations it may be even better...