HP vs. TQ
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HP vs. TQ
Ok both horsepower and torque are obviously important factors of having a fast car along with a couple other variables. Which is MORE important? Why would you say not want to build a higher torque motor vs. a higher horse power motor? All anyone really talks about is how much hp someone has. I'd like to have a good explanation on why each is important, which is "better", and also how do you build a "torquer" motor? I figured this was the best place for the thread. Thanks
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Uh oh! We have a lot of these threads and they always turn out bad.
Which is more important?
HP = (TQ x RPM) / 5252
Therefore, TQ is one of the variables when calculating HP, so how can one be more important than the other when they are related in that manner? I guess you could technically say HP is more important because it includes TQ and RPM's.
TQ is your force that a complete stroke of the engine produces and RPM is just the number of complete strokes your engine can make in a certain amount of time. I can't explain it very well. Just read the HP vs TQ sticky.
The official sticky
Page 1: https://ls1tech.com/forums/showpost....1&postcount=32
Page 2: https://ls1tech.com/forums/showpost....2&postcount=33
Which is more important?
HP = (TQ x RPM) / 5252
Therefore, TQ is one of the variables when calculating HP, so how can one be more important than the other when they are related in that manner? I guess you could technically say HP is more important because it includes TQ and RPM's.
TQ is your force that a complete stroke of the engine produces and RPM is just the number of complete strokes your engine can make in a certain amount of time. I can't explain it very well. Just read the HP vs TQ sticky.
The official sticky
Page 1: https://ls1tech.com/forums/showpost....1&postcount=32
Page 2: https://ls1tech.com/forums/showpost....2&postcount=33
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HP is a cralculation, and just that... An engine produces an amount of torque, and the dyn then uses that equation HP=(TQxRPM)/5252 and wherever the HP is the highest, it reports back with that RPM and what the HP was.
Therefore, an engine doesnt MAKE horsepower, it makes torque.
Look at it this was, F1 cars only make like 250 ft/lbs of torque, but because it is at like 17000 rpms, they make a lot of HP.
So, TQ gets you moving, and keeping a broader powerband of a lto of torque at the higher RPMS(HP) keeps you moving.
Therefore, an engine doesnt MAKE horsepower, it makes torque.
Look at it this was, F1 cars only make like 250 ft/lbs of torque, but because it is at like 17000 rpms, they make a lot of HP.
So, TQ gets you moving, and keeping a broader powerband of a lto of torque at the higher RPMS(HP) keeps you moving.
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Originally Posted by Sk8runeg
HP is a cralculation, and just that... An engine produces an amount of torque, and the dyn then uses that equation HP=(TQxRPM)/5252 and wherever the HP is the highest, it reports back with that RPM and what the HP was.
Therefore, an engine doesnt MAKE horsepower, it makes torque.
Therefore, an engine doesnt MAKE horsepower, it makes torque.
Let's say we have a car and the engine makes 300 lb/ft of torque at 1 RPM. The engine rotates once per minute, making the 300 lb/ft only one time in an entire minute. I hope to God that you can see that this 300 lb/ft of torque is not going to get you to the grocery store any time this century.
Now let's say another engine in the same type of car is making 300 lb/ft at 100 RPM. It is making that 300 lb/ft 100 times every minute. It will be moving much faster, yet still slow as hell.
Now a 3rd engine in the same type of car is also making 300 lb/ft, but it is making it at 7000 RPM. It is making that same 300 lb/ft force, 7000 times every minute. Now this car is MOVING!
In each case the various engines were making 300 lb/ft of torque, but 1 would barely be lunging once a minute, the second is going much faster than the first but would still be moving stupidly slow, and the 3rd is flying down the road at a buck 80 to Grandmother's house we go.
HP = (TQ x RPM)/5252 just like you said, but do you see what it means? Your horsepower equals the force your engine makes for a cycle, times the number of cycles it can make in a minute's time, divided by a constant (5252) that compensates for the unit conversion factors.
Last edited by Louie83; 08-04-2006 at 11:07 PM.
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my car is an ls1 with top end and all that horsepower.
My brothers 88 transam has a 383 which we built to put down crazzy torque.
You know night and day the differences,his car just murders me off the line,specially because he has slicks and a 3500 stall.But once we hit 75mph and i just hit 3rd gear,i zip past him like a bat outta hell.
A stroker is an easy way to build a torque monster.
My brothers 88 transam has a 383 which we built to put down crazzy torque.
You know night and day the differences,his car just murders me off the line,specially because he has slicks and a 3500 stall.But once we hit 75mph and i just hit 3rd gear,i zip past him like a bat outta hell.
A stroker is an easy way to build a torque monster.
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Don't debate it.... They're both important.
The key to understanding is remembering that engine speed and vehicle speed will determine where you want to make torque. Horsepower curves confuse the hell out of most people, so when in doubt throw it away and just look at the torque curve (and don't forget it's compared against engine speed).
To make the best use of torque you have to determine how fast you want your car to go. At the same time, determine how fast you want your engine to spin. Gear the car to use the most of your power curve, and the result will be maximized torque to the wheels. This is the way I always try to think of it. Maximize torque to the wheels, and maximize power from the engine, all within your using range.
So many factors come into play that we forget about how a car can be optimized in the real world. We're all working with stock block engines, street cars, availabe aftermarket parts, and budgets, so we'll never reach an optimum set up. Also, we have a tendency to aspire to good throttle response, which means lots of torque at low vehicle and engine speeds.
At the end of the day, don't get too caught up in the debate. Just make a powerful, fun driving car that outruns all of your friends cars, and your work is done.
The key to understanding is remembering that engine speed and vehicle speed will determine where you want to make torque. Horsepower curves confuse the hell out of most people, so when in doubt throw it away and just look at the torque curve (and don't forget it's compared against engine speed).
To make the best use of torque you have to determine how fast you want your car to go. At the same time, determine how fast you want your engine to spin. Gear the car to use the most of your power curve, and the result will be maximized torque to the wheels. This is the way I always try to think of it. Maximize torque to the wheels, and maximize power from the engine, all within your using range.
So many factors come into play that we forget about how a car can be optimized in the real world. We're all working with stock block engines, street cars, availabe aftermarket parts, and budgets, so we'll never reach an optimum set up. Also, we have a tendency to aspire to good throttle response, which means lots of torque at low vehicle and engine speeds.
At the end of the day, don't get too caught up in the debate. Just make a powerful, fun driving car that outruns all of your friends cars, and your work is done.
#11
I remember when I started a thread like this on camaroz28.com back in like 1998. I think among the part 1, 2, 3, 4, and 5 threads.. it breached over 2000 total posts. What a gem
I wish I could still read those.
I wish I could still read those.