performance inhancer study that needs verification
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Joined: Dec 2006
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From: Sask. Canada
Originally Posted by Labnerd
Uh, no. If torque was the key to speed a Peterbuilt with a V10 CAT would blow the doors off of a new Bugatti. Torque equates to pulling power. Horsepower equates to speed. There is also the factor of diminished returns. Depending on the application, doubling HP may only net you extremely small returns. Case in point would be a jet boat. Getting to 60 mph is fairly easy, getting to 120 requires extreme amounts of HP and doubling HP won't get you but maybe 10-15 mph faster. A 500 HP gas engine in a Peterbuilt won't pull a normal load for the rig wheras a 300 HP diesel with 800 lbs torque pulls it with ease. If you go up on tire size and you want to increase speed, you have to go up on both HP and torque. Make sense? If you are looking to build a rig of any kind you don't start with the engine, you start at the back tires and work your way forward. Once you know the tires size, determine the axle ratio which depends on the transmission. Now you know what the requirements are for the engine you need to build. Most street folks do just the opposite and wonder why they get beat by much smaller but better thought out vehicles.
hp=tq*rpm/5252
so he is right when he says that he needs to increase the tourque of the vehicle to gain more speed/acceleration.
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Joined: Aug 2007
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From: Rohnert Park, CA
Originally Posted by INFireRedF150
Well, each person understands things a little different. I would say, from my point of view, that combustion is a controlled explosion of something, and detonation is an uncontrolled explosion of something. 
I just remember gettin in a fat debate with my old shop teacher. I used an answer with "explosion" in it and he lectured me about how it wasn't for EVER.... so i will never use that term again...
Last edited by MercedesTech; Nov 20, 2007 at 11:22 PM.
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From: AZ
As usual LabNerd is right on the money. Changing gearing increase or decreases the torque multiplication.
Torque multiplication explains why in the 1950's and early 60's a diesel truck running 190 HP and 600 -800 lb-ft of torque could pull a load of 40,000 lbs all over the country. Just not real fast. Most of the 1 ton diesel pickups have as much HP and torque as the old semi's had in the 50's. GM evn made 140 HP 2 stroke diesels for trucks.
Torque multiplication explains why in the 1950's and early 60's a diesel truck running 190 HP and 600 -800 lb-ft of torque could pull a load of 40,000 lbs all over the country. Just not real fast. Most of the 1 ton diesel pickups have as much HP and torque as the old semi's had in the 50's. GM evn made 140 HP 2 stroke diesels for trucks.