Quote:
Originally Posted by Stephen12ZL1
Mostly due to the camshaft profile. Sometimes it is due to the dyno variations. My car usually is slightly more torque vs hp with the stock cam. Some of the camshafts that peak at higher rpm usually show less peak torque.
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Yes. Exactly this. Larger cams with more duration can carry the torque out to a higher RPM. And you must understand the relationship between HP an TQ. TQ is the twisting force of the tires on the pavement. That's what propels your car. I.E. torque is angular force. Now HP is calculated from TQ.
HP=(TQ x RPM)/5250
From this you can see that because TQ is multiplied times RPM that the same amount of TQ at a higher RPM results in a lot more HP. Also the nature of this equation is why the HP and TQ curves always cross at 5250 RPM.
This is why a diesel engine that makes massive TQ at low rpm doesn't equate to much HP. Say a turbo diesel truck makes 700 ft-lb of torque at a low 2000 RPM.
(700 x 2000)/5250=260HP
Only 260 HP!
Now see in my car how a bigger cam with all other things constant (same boost etc.) makes way more TQ the faster you spin the engine. This results in some increase in peak TQ but a big increase in HP.