torque vs bhp, their relationship/ratio... what does this mean?

[badger5]

torque vs bhp, their relationship/ratio... what does this mean?

what I mean is when a turbo motor produces more power than torque, comparing bhp for lbft in unit terms, what does it mean when for example the turbo produces more torque than bhp, and visa versa?

to use an example.. k03s when tuned could do 220bhp and 250lbft torque but an IHI VF34 could do 320bhp and 280lbft torque, and in a more extreme case, 489bhp with 355lbft torque

What does this tell me?

[20V18Tnut]

It just says at what RPM range the maximun power is produced. hp=(tq x rpm)/5252
tdi cars produce tonns of tq but tdi motors only rev to 5000rpm, so that's why you see 90hp/150tq, honda high revving motors make very sparse tq but very impressive hp just to sample a few.

[transient]

from vortex:

everyone has been talking about theory, so I was bored and made this with scilab (no matlab at work :/) so that we can all visualize what's going on.  Sorry for the large picture:



I took a dyno run and used the tq-rpm-hp values to make a 3d trace on a theoretical surface created by:

HP = torque' * rpm /5250;

or

z = y' * x /constant.

where x and y are 1xN vectors.. and z is an NxN matrix (duh).

It's a really stupid looking surface, but it explains alot when you plot traces on top of it (like the dyno info).  I think the torque vs hp curve is the most interesting.

if anyone has an excel file of a dyno (tq, hp and rpm), I'll add it to this chart and try to use a different color (scilab is a biznitch to get plot formatting correct).

It would be really cool to see some NA cars, and some high horsepower cars plotted on this too.