Yes you can. You increase horsepower at a given RPM by making more torque. But, what usually happens with camshafts is, make more horsepower by maintaining torque and revving an engine higher. Horsepower is a calculated, derived output based exclusively by torque at a given RPM. Therefore, you don't need to make MORE torque to make horsepower, you just need to maintain torque and make more revs.
You can actually make less torque as well, so long as your revs are high enough.
Case in point - BMW motor making 175 tq at 6800 RPM makes 226 bhp. A formula 1 car making 175 tq at 18,000 RPM makes 600 bhp. I just increased horsepower without making a change to torque at all. The majority of aftermarket cam shafts have the same or maybe slightly more lift, but a good bit more duration - this helps keep the engine breathing once the pistons start flying. The motors don't make much more torque at all, they just don't fall off like they do on stock cams, and therefore since HP = ( tq x rpm)/5252, and they hold their torque at a higher RPM, horsepower goes up. But again, horsepower is just a derived number. If you had an engine that made 175 ft lb @ 6800 and an engine that makes only 90 ft lb at 18,000 the 90 ft lb would STILL make 310 hp. But that goes against what you claimed :)
Its the same reason why a 700 hp HPF car will lose a race to an E36 M5x/S5x (non s54) car with 700 hp. The reason the HPF cars make so much horsepower is because the formula works to their advantage taking relatively weak torque numbers (for what they are) but running 8500 RPM. An S54 only needs to make 433 ft/lb to be a 700 hp car whereas a lower revving M50 variant... to be called a 700 hp car, needs to be producing 540 ft lb of torque at redline, which is a much more powerful engine given the redline is closer to 6800 - 7000. If you ran the S54 to 6800 RPM its only a 560 hp motor, not nearly as impressive. So a cam provides more horsepower not by increasing torque, but by maintaining it. If your car made 200 tq at 5200 RPM and fell off to 180 by 7000, and a new cam made 200 tq at 5200 RPM and fell off to only 190 by 7000, you didn't "make more torque" in terms of peak numbers, you just kept it from falling off... increasing the calculated horsepower.
I didn't say that lift hurt low end torque, it almost always does not, however longer duration almost always does. Being that this instance is not about VANOS I did not feel it was necessary to bring that up.
You can actually make less torque as well, so long as your revs are high enough.
Case in point - BMW motor making 175 tq at 6800 RPM makes 226 bhp. A formula 1 car making 175 tq at 18,000 RPM makes 600 bhp. I just increased horsepower without making a change to torque at all. The majority of aftermarket cam shafts have the same or maybe slightly more lift, but a good bit more duration - this helps keep the engine breathing once the pistons start flying. The motors don't make much more torque at all, they just don't fall off like they do on stock cams, and therefore since HP = ( tq x rpm)/5252, and they hold their torque at a higher RPM, horsepower goes up. But again, horsepower is just a derived number. If you had an engine that made 175 ft lb @ 6800 and an engine that makes only 90 ft lb at 18,000 the 90 ft lb would STILL make 310 hp. But that goes against what you claimed :)
Its the same reason why a 700 hp HPF car will lose a race to an E36 M5x/S5x (non s54) car with 700 hp. The reason the HPF cars make so much horsepower is because the formula works to their advantage taking relatively weak torque numbers (for what they are) but running 8500 RPM. An S54 only needs to make 433 ft/lb to be a 700 hp car whereas a lower revving M50 variant... to be called a 700 hp car, needs to be producing 540 ft lb of torque at redline, which is a much more powerful engine given the redline is closer to 6800 - 7000. If you ran the S54 to 6800 RPM its only a 560 hp motor, not nearly as impressive. So a cam provides more horsepower not by increasing torque, but by maintaining it. If your car made 200 tq at 5200 RPM and fell off to 180 by 7000, and a new cam made 200 tq at 5200 RPM and fell off to only 190 by 7000, you didn't "make more torque" in terms of peak numbers, you just kept it from falling off... increasing the calculated horsepower.
I didn't say that lift hurt low end torque, it almost always does not, however longer duration almost always does. Being that this instance is not about VANOS I did not feel it was necessary to bring that up.
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