Time for a Torque and H\P lesson!!!!
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From: KY
Time for a Torque and H\P lesson!!!!
I'm not the one to do it but I know there are those here who can.
Regarding the ported blowers, so far we are seeing the same or lower torque numbers after porting or compared to a L without a port job.
Don't we want to raise our torque #'s?
Isn't our incredible torque #'s at low rpms what gives us our edge?
Regarding the ported blowers, so far we are seeing the same or lower torque numbers after porting or compared to a L without a port job.
Don't we want to raise our torque #'s?
Isn't our incredible torque #'s at low rpms what gives us our edge?
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From: South East USA
With mods you are making more HP than stock...and more torque....How do you figure you are loosing torque?
Let me know if you make more torque with an unported Eaton than you do with a ported one......
Let me know if you make more torque with an unported Eaton than you do with a ported one......
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From: Florida
I think in this whole dyno thing people are missing a big part of the #'s. Everybody is looking at peak #'s But, no one is looking at where these #'s are(RPM) and they are not looking at the rest of the graph.
I have a ported eaton, and just went to the dyno this weekend. After tuning I ended up with 439hp 513tq SAE Well; the torque #'s are low, but if you look at the graph the tq curve is very high and very flat meaning the tq is there from way down low to way up high. The HP is pretty good; but what was amazing is the peak HP was around 5100~5200 RPM which means the blower is being pretty efficient.
Actual #'s before correction were 460/530; can't wait till the track this weekend
Mods were Filter, Predator(tuned by RWTD), #4 lower, Wes ported eaton, dynatech full exhaust, SBTB, and a few small things. A/F was 11.7 nice and flat
I have a ported eaton, and just went to the dyno this weekend. After tuning I ended up with 439hp 513tq SAE Well; the torque #'s are low, but if you look at the graph the tq curve is very high and very flat meaning the tq is there from way down low to way up high. The HP is pretty good; but what was amazing is the peak HP was around 5100~5200 RPM which means the blower is being pretty efficient.
Actual #'s before correction were 460/530; can't wait till the track this weekend
Mods were Filter, Predator(tuned by RWTD), #4 lower, Wes ported eaton, dynatech full exhaust, SBTB, and a few small things. A/F was 11.7 nice and flat
Last edited by Casey02L; Mar 3, 2004 at 12:41 PM.
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From: At the Gas Pump!
A torque peak at low rpm will get you out of the hole and produce a great 60ft time. After that, the rpms never drop low enough to matter. Moving the torque peak up is better for drag racing, but of little use on the street. Extending the torque peak, and increasing the area under the curve is the best of both worlds.
It seems the the ported Eatons are sacrificing a little bit of peak torque at 3000 rpm in order to make substantial gains in the 3800 rpm and up range. This added hp and torque should be useable at the track, since it falls into a rpm range that will be used in all gears instead of just one.
It seems the the ported Eatons are sacrificing a little bit of peak torque at 3000 rpm in order to make substantial gains in the 3800 rpm and up range. This added hp and torque should be useable at the track, since it falls into a rpm range that will be used in all gears instead of just one.
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From: Arkansas
Somewhere lurking out there is a lawyer from California who's going to pipe up and tell you torque is meaningless and horsepower wins races. Which overlooks the fact that a dyno measures torque and horsepower is calculated from torque. Yes, torque gets you out of the hole and gets you on your way down the track quicker. Broading the torque curve and moving the torque peak up to a higher rpm equates to more HP at higher rpm and total HP under the curve, and higher quarter mile speeds.
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From: Austin, TX
Originally posted by SVTARKANSAS
Which overlooks the fact that a dyno measures torque and horsepower is calculated from torque.
Which overlooks the fact that a dyno measures torque and horsepower is calculated from torque.
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Originally posted by SVTARKANSAS
Somewhere lurking out there is a lawyer from California who's going to pipe up and tell you torque is meaningless and horsepower wins races.
Somewhere lurking out there is a lawyer from California who's going to pipe up and tell you torque is meaningless and horsepower wins races.
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From: Selden NY
I still wanna know who all these alleged people are that lost torque with the PE Mod ??? This is the second post I've seen recently about it and to Date I know of NO-ONE that isn't happy
with the gains of a Ported Eaton. Everyone is just antsy because
Racing season hasn't started and the ET's aren't flying in yet.
GIVE IT TIME, THE NUMBERS WILL BE THERE
Listen for $300.00 I be happy as pig in schitt with anywhere from 20-40 HP and 10-20 additional lbs of Torque gain from my WASP. Like EVERYONE is saying, "and EVERY after Dyno has proved", a Ported Eaton DOES now have MORE power, and it DOES carry it to a much higher (and race track usable) RPM.
SOME PEOPLE ARE NEVER HAPPY.............
If my motor holds together, you will get a true before and after
ET Diff from me next time out. By squirting Sub Zero into the Motor (aka/Nitrous) you create an extremly consistant run,
time after time, (thats why I only make 1-2 passes)
I aint gonna improve on the run before if I hooked.
Unfortunatly they took the only track we had away @*$#*(@#$
so I have to wait another month.....
When I go back to Cecil, it will be on 4lbs only, and the same 65 HP Jets. (ran (2) 12.0's last time) Yes I ran an 11.81 at Eng Town, but that was with 75HP Jets and 6lbs. I wil not be using that set up on Nitrous anymore. I do not want to go faster than that,
(not on a stock motor) I only ask of this WASP to alow me to run the same 11.8 but with 2less lbs of Boost, and 10 less Nitrous HP.
I already know it will
with the gains of a Ported Eaton. Everyone is just antsy because
Racing season hasn't started and the ET's aren't flying in yet.
GIVE IT TIME, THE NUMBERS WILL BE THERE
Listen for $300.00 I be happy as pig in schitt with anywhere from 20-40 HP and 10-20 additional lbs of Torque gain from my WASP. Like EVERYONE is saying, "and EVERY after Dyno has proved", a Ported Eaton DOES now have MORE power, and it DOES carry it to a much higher (and race track usable) RPM.
SOME PEOPLE ARE NEVER HAPPY.............
If my motor holds together, you will get a true before and after
ET Diff from me next time out. By squirting Sub Zero into the Motor (aka/Nitrous) you create an extremly consistant run,
time after time, (thats why I only make 1-2 passes)
I aint gonna improve on the run before if I hooked.
Unfortunatly they took the only track we had away @*$#*(@#$
so I have to wait another month.....
When I go back to Cecil, it will be on 4lbs only, and the same 65 HP Jets. (ran (2) 12.0's last time) Yes I ran an 11.81 at Eng Town, but that was with 75HP Jets and 6lbs. I wil not be using that set up on Nitrous anymore. I do not want to go faster than that,
(not on a stock motor) I only ask of this WASP to alow me to run the same 11.8 but with 2less lbs of Boost, and 10 less Nitrous HP.
I already know it will
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From: KY
I will be a happy camper with a 20-30hp gain for $300.
and even happier if it knocks a tenth off my 1\8th and gets me to a 7.99.
Ansy, YES!! and being unable to drive my L is driving me crazy.
>>SOME PEOPLE ARE NEVER HAPPY.............
Uhhhhh Rob, what were your mods again
and even happier if it knocks a tenth off my 1\8th and gets me to a 7.99.
Ansy, YES!! and being unable to drive my L is driving me crazy.
>>SOME PEOPLE ARE NEVER HAPPY.............
Uhhhhh Rob, what were your mods again
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Joined: Feb 2001
Posts: 1,394
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From: San Antonio
Originally posted by 0light1
I will be a happy camper with a 20-30hp gain for $300.
and even happier if it knocks a tenth off my 1\8th and gets me to a 7.99.
Ansy, YES!! and being unable to drive my L is driving me crazy.
>>SOME PEOPLE ARE NEVER HAPPY.............
Uhhhhh Rob, what were your mods again
I will be a happy camper with a 20-30hp gain for $300.
and even happier if it knocks a tenth off my 1\8th and gets me to a 7.99.
Ansy, YES!! and being unable to drive my L is driving me crazy.
>>SOME PEOPLE ARE NEVER HAPPY.............
Uhhhhh Rob, what were your mods again
stated in the context of modding and complaining about gains......Dose not apply to Rob.
Originally posted by 0light1
Don't we want to raise our torque #'s?
Isn't our incredible torque #'s at low rpms what gives us our edge?
Don't we want to raise our torque #'s?
Isn't our incredible torque #'s at low rpms what gives us our edge?
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From: TEXAS
Originally posted by kdanner
If you're talking about a dynojet dyno, you're wrong. Go run your truck on one but don't use the inductive RPM pickup. You'll get HP, but not torque. The HP and RPM is used to calculate torque, not the other way around.
If you're talking about a dynojet dyno, you're wrong. Go run your truck on one but don't use the inductive RPM pickup. You'll get HP, but not torque. The HP and RPM is used to calculate torque, not the other way around.
The twisting force on the drums is what is measured -That is torque
References...
http://www.dynamometerservices.com/FAQ2.htm
How does a dynamometer work?
If you want to know the horsepower of an engine, you hook the engine up to a dynamometer (or dyno). A dyno places a load on the engine and measures the amount of power that the engine can produce against the load. Imagine it like this: if you started your engine, had no load on it and floored it, it would run so fast it would explode. So, on the dyno, you apply a load to the floored engine and measure the load that the engine will handle at different speeds. The dyno takes hundreds of readings throughout the rpm spectrum and then measures the torque that the engine can pull against the drum. Then, it instantaneously calculates horsepower from the torque and plots it all on one graph.
If you want to know the horsepower of an engine, you hook the engine up to a dynamometer (or dyno). A dyno places a load on the engine and measures the amount of power that the engine can produce against the load. Imagine it like this: if you started your engine, had no load on it and floored it, it would run so fast it would explode. So, on the dyno, you apply a load to the floored engine and measure the load that the engine will handle at different speeds. The dyno takes hundreds of readings throughout the rpm spectrum and then measures the torque that the engine can pull against the drum. Then, it instantaneously calculates horsepower from the torque and plots it all on one graph.
http://www.revsearch.com/dynamometer/why_dyno_test.html
To get accurate horsepower and torque numbers.
A computerized engine dynamometer accurately measures torque and rpm and then can accurately calculate horsepower.
A computerized engine dynamometer accurately measures torque and rpm and then can accurately calculate horsepower.
http://www.dynoshop.com/dynotest.htm
DATA INPUT
Each dynomometer drum has a sensor which reads the energy transfered from the drive wheels of your vehicle. The horsepower is then calculated by the computer by measuring the drum acceleration.
Each dynomometer drum has a sensor which reads the energy transfered from the drive wheels of your vehicle. The horsepower is then calculated by the computer by measuring the drum acceleration.
What is a dynamometer?
A dynamometer is a device that measures force and power. There are lots of different kinds of dynamometers, including the kind that test springs and shocks, but we don't care about them because I don't have any. I have an inertia-type chassis dynamometer. It measures the force and power that the spinning wheels of an automobile produce. It is not a "brake-type" dyno that measures the power that is actively absorbed by a water, oil, or eddy-current brake or by a generator. An inertia-type chassis dyno consists of two great big heavy drums hooked up to a computer. The wheels of an automobile spin the dyno drums, and the computer measures the speed.
Simple? If you remember the stuff you were supposed to learn in high school, it is. The computer calculates the acceleration of the dyno drums by continuous measurements of their speed and the time. If the surface of the drums spin from a speed of zero to a speed of 10 feet per second in one second, then their surface acceleration is 10 feet per second per second, or 10 ft/s2. Sound familiar?
Force = Mass x Acceleration
That's one of Newton's laws. It's not important which one it is, because I don't remember. Force is one of the things that we're looking for. Force in the automotive world is called - you're supposed to shout it out..... torque. Torque is rotational force, and its most common unit for us is foot-pounds. Plain and simple, if you have a 12-inch wrench and you lean on the very end of the handle with 10 pounds, you're applying a force of 10 ft-lb. to the nut you're trying to turn.
The mass in our case gets a bit complicated. Mass in most cases is easy - how much does the object weigh that you're accelerating. In the case of the dyno drums, however, it's not that simple because we are not "moving" the drum, we're spinning it. We are not creating a "translational" motion on the drum, we are creating a "rotational" motion. To understand the difference, think of the actual dyno drums. Each one weighs 2700 pounds. It would take a pretty impressive force to push a 2700 lb. object across the floor. Now imagine just spinning those drums. The shaft going through the center of the drums rests on two hugely expensive bearings that I'm probably going to have to replace a lot more often than I want to. The drums spin with the slightest touch. To calculate away this difference, physicists came up with the "mass equivalent" of a rotating body, which is very similar to the "moment of inertia." I don't know the actual numbers, but let's just pretend the mass equivalent of the dyno drum is 50 pounds. That means that spinning the 2700 lb. drum is like pushing a 50 lb. weight across the floor (forget about the friction - you nerd.) Now I've heard some people say that this is not the correct way for calculating horsepower, but in this case - it is. Many of you are familiar with the hp = rpm x torque / 5252 formula. In many situations, that formula is the way horsepower is calculated. In the case of the Dynojet dynamometer, it is not. The Dynojet calculates horsepower even if there is no torque reading, and it does this in the manner that I am in the process of describing. Those of you that have had your vehicles tested at my shop and have watched the computer screen closely have seen that the computer plots out only the horsepower after each run, and I have to click the mouse a few times to get your torque. It does this because sometimes there is no torque reading, or the torque reading is faulty. This can happen because inductive and optical rpm pickups may not be perfect, and/or your ignition system may make things go a little haywire. If the rpm readings are not perfect, and the computer used the rpm x torque / 5252 formula, the hp reading would be inaccurate.
Work = Force x Distance
Now we get to the good stuff. Calculating the work is pretty simple for the computer. It just figured out the force, and it can easily figure out the distance because it knows the circumference of the drum and how many times it has rotated.
Power = Work / Time
We have an answer. Somewhere the computer factored in the bearing drag, and it throws some constants into those formulas to get the numbers to come out into the right units, but you get the idea.
A dynamometer is a device that measures force and power. There are lots of different kinds of dynamometers, including the kind that test springs and shocks, but we don't care about them because I don't have any. I have an inertia-type chassis dynamometer. It measures the force and power that the spinning wheels of an automobile produce. It is not a "brake-type" dyno that measures the power that is actively absorbed by a water, oil, or eddy-current brake or by a generator. An inertia-type chassis dyno consists of two great big heavy drums hooked up to a computer. The wheels of an automobile spin the dyno drums, and the computer measures the speed.
Simple? If you remember the stuff you were supposed to learn in high school, it is. The computer calculates the acceleration of the dyno drums by continuous measurements of their speed and the time. If the surface of the drums spin from a speed of zero to a speed of 10 feet per second in one second, then their surface acceleration is 10 feet per second per second, or 10 ft/s2. Sound familiar?
Force = Mass x Acceleration
That's one of Newton's laws. It's not important which one it is, because I don't remember. Force is one of the things that we're looking for. Force in the automotive world is called - you're supposed to shout it out..... torque. Torque is rotational force, and its most common unit for us is foot-pounds. Plain and simple, if you have a 12-inch wrench and you lean on the very end of the handle with 10 pounds, you're applying a force of 10 ft-lb. to the nut you're trying to turn.
The mass in our case gets a bit complicated. Mass in most cases is easy - how much does the object weigh that you're accelerating. In the case of the dyno drums, however, it's not that simple because we are not "moving" the drum, we're spinning it. We are not creating a "translational" motion on the drum, we are creating a "rotational" motion. To understand the difference, think of the actual dyno drums. Each one weighs 2700 pounds. It would take a pretty impressive force to push a 2700 lb. object across the floor. Now imagine just spinning those drums. The shaft going through the center of the drums rests on two hugely expensive bearings that I'm probably going to have to replace a lot more often than I want to. The drums spin with the slightest touch. To calculate away this difference, physicists came up with the "mass equivalent" of a rotating body, which is very similar to the "moment of inertia." I don't know the actual numbers, but let's just pretend the mass equivalent of the dyno drum is 50 pounds. That means that spinning the 2700 lb. drum is like pushing a 50 lb. weight across the floor (forget about the friction - you nerd.) Now I've heard some people say that this is not the correct way for calculating horsepower, but in this case - it is. Many of you are familiar with the hp = rpm x torque / 5252 formula. In many situations, that formula is the way horsepower is calculated. In the case of the Dynojet dynamometer, it is not. The Dynojet calculates horsepower even if there is no torque reading, and it does this in the manner that I am in the process of describing. Those of you that have had your vehicles tested at my shop and have watched the computer screen closely have seen that the computer plots out only the horsepower after each run, and I have to click the mouse a few times to get your torque. It does this because sometimes there is no torque reading, or the torque reading is faulty. This can happen because inductive and optical rpm pickups may not be perfect, and/or your ignition system may make things go a little haywire. If the rpm readings are not perfect, and the computer used the rpm x torque / 5252 formula, the hp reading would be inaccurate.
Work = Force x Distance
Now we get to the good stuff. Calculating the work is pretty simple for the computer. It just figured out the force, and it can easily figure out the distance because it knows the circumference of the drum and how many times it has rotated.
Power = Work / Time
We have an answer. Somewhere the computer factored in the bearing drag, and it throws some constants into those formulas to get the numbers to come out into the right units, but you get the idea.
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From: KY
>>did you read where someone lost torque with a ported eaton compared to a non-ported eaton ?
No, only that a non ported eaton seems to provide the same torque at lower rpm's and the gain seems to be H\P at higher rpm's. I was under the impression that torque is what we like to see go up.
it seems though I dont know what I'm talking about. So, I will just wait and see when I get mine back from being ported
No, only that a non ported eaton seems to provide the same torque at lower rpm's and the gain seems to be H\P at higher rpm's. I was under the impression that torque is what we like to see go up.
it seems though I dont know what I'm talking about. So, I will just wait and see when I get mine back from being ported
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From: Austin, TX
Originally posted by Silver_2000_
!
Uh NO...
! Uh NO...
I think you should go read your own post where you pasted in:
Many of you are familiar with the hp = rpm x torque / 5252 formula. In many situations, that formula is the way horsepower is calculated. In the case of the Dynojet dynamometer, it is not. The Dynojet calculates horsepower even if there is no torque reading
Last edited by kdanner; Mar 5, 2004 at 02:12 AM.