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  #16 (permalink)  
Old 05-11-2010, 02:42 PM
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What I'm saying is that it doesn't matter what your operating range is, you can take a look at your horsepower curve, determine how much time you can spend effectively at each point and you can describe your run that way. All other things equal a 400 horse V8 will get to the end of a 1/4 before a 400 horse 4 banger because there is more area under curve for the motor's horsepower at more time points throughout the curve. You can certainly describe that phenomenon by talking about torque, which is work, and a multiplier for power.

I don't think the folks on this forum necessarily need an educational thread about this. If they have a question, they're grown-ups and they can ask.

K

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  #17 (permalink)  
Old 05-11-2010, 02:48 PM
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Quote:
Originally Posted by killerformula
What I'm saying is that it doesn't matter what your operating range is, you can take a look at your horsepower curve, determine how much time you can spend effectively at each point and you can describe your run that way. All other things equal a 400 horse V8 will get to the end of a 1/4 before a 400 horse 4 banger because there is more area under curve for the motor's horsepower at more time points throughout the curve. You can certainly describe that phenomenon by talking about torque, which is work, and a multiplier for power.

I don't think the folks on this forum necessarily need an educational thread about this. If they have a question, they're grown-ups and they can ask.

K

That 4 banger could VERY easily have more power under the curve. But at least I know that you realize the average power is important. Torque is NOT a multiplier of power... I don't know where you got that one from so I'll just leave it at that. Also, torque is not work. Torque, work, and power are 3 very different things.

And I would say that understanding why and how to go fast is something that many members on this forum would like a thread about... The nice thing about a forum is people are allowed to express their opinions, whether they are insightful or misleading.
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  #18 (permalink)  
Old 05-11-2010, 03:04 PM
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torque and power are very different? One horsepower is 550 lb/ft of torque per second. You can certainly describe horsepower by torque.

Wonderful, yes there are exceptions to every rule. Hence saying all things being equal and 400 horse, which means that the V8 would win, every time. No exceptions. Obviously professor AP is out to stir the pot today...

Have fun!

K
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Old 05-11-2010, 03:11 PM
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KILLERFFORMULA do you shift at 10 % past peak torgue with your mopars? I know most say shift at 10 % past peak hp, but i know , from my expirence is that the mopar guys shift at 10 % past torgue peak . Here at least by me they do .
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  #20 (permalink)  
Old 05-11-2010, 03:17 PM
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Quote:
Originally Posted by crystalbluevib
KILLERFFORMULA do you shift at 10 % past peak torgue with your mopars? I know most say shift at 10 % past peak hp, but i know , from my expirence is that the mopar guys shift at 10 % past torgue peak . Here at least by me they do .
Sure, same concept, I would assume most people shift after the peak because your average power per time is higher when you do that than if you shift at the peak.

K
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  #21 (permalink)  
Old 05-11-2010, 03:42 PM
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What I said about Bob Glidden isn`t hear say, that`s fact.
One of the biggest misconceptions in this country is education means wisdom and that`s not true in any shape or form. They don`t teach common sense in college. Education without common sense is useless. Blind leading the blind? Lets see, Nobody follows me because I don`t let them, I`m a loner in that respect, and I don`t go preaching what I believe or try to continously get something going based on Theory. Some theories are interesting, but this isn`t very. If the goal of your posts such as this is to make others look like a fool just to show what you know isn`t a very wise idea, you`ll make alot of enemies that way. As far as myself, I dropped out in the 9th grade but it`s funny,, I build computers, I do automotive work, I build car and home audio systems, and the list goes on and on and I learned these things myself, nobody taught me. So yeah, I`m undereducated, but I`m far from stupid.
From what I see AP, you act like you got something to prove to everybody just because you feel the need to make yourself look better. If you want this whole board to yourself, then fine, I`ll leave to just make it easier on you.
When your wrong, you can`t believe your wrong, maybe because your book said so or such and such said so, you believed a solid lifter flat tappet cam was better than a hydraulic roller so which blind person lead you?
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  #22 (permalink)  
Old 05-11-2010, 03:44 PM
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Quote:
Originally Posted by killerformula
torque and power are very different? One horsepower is 550 lb/ft of torque per second. You can certainly describe horsepower by torque.

Wonderful, yes there are exceptions to every rule. Hence saying all things being equal and 400 horse, which means that the V8 would win, every time. No exceptions. Obviously professor AP is out to stir the pot today...

Have fun!

K


AP i have to agree with killerformula here

now for another one of those "hear-say" quotes. " torque is what gives you your 1/4 time but hp is what gives you your trap speed"

i do understand the idea of "well if it's all about tq then why aren't all racers using desiels" i would say that when it comes right down to it that you need a healthy combination of the two to really win the race, cause you can have all the horsepower you want but no tq (ie high rpm short stroke imports) and still get beat by a vehicle that turns less rpm and has less peak hp simply beacuse it makes good tq all the way across the curve, and we know that hp= tq x RPM / 5252. so with the desiels since they only trun say 3000rpm it's hard for them to make high amounts of hp beacuse it does take rpm to make hp. and for the imports all of their power is concentrated high in the rpm band and only really lasts for about 2000rpm, while in a decent street/stip SBC it's not that hard to keep atleast 400+lb ft of tq from 2500rpm through 6000+ rpm and as long as you can keep decent tq all the way throught the curve then you will obvously make decent hp all the way throught the curve.

this may have been a little all over the place but really i'm agreeing with the idea of more average hp/tq across the entire rpm band from shift to shift will win the race
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Old 05-11-2010, 03:54 PM
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What was that line from Jaws? The one about not having enough sense to admit your wrong? I thought I knew everything when I was 18...not 24. But hell, maybe we are all wrong and your right. Good grief.
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Old 05-11-2010, 04:20 PM
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Quote:
Originally Posted by ap72
true, you need some tq to make power, but having an infinite amount of torque with no power can't move a flea...
wrong, from it's stopped position a bigboy steam locomotive made around 200,000 fpt @ 0 rpm & 0 horsepower.
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Old 05-11-2010, 04:39 PM
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I guess "The Genius" cant argue this anymore. Signed off. What do the kids type nowadays??? LOL? LMAO? ROTFL?
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Old 05-11-2010, 06:48 PM
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Double Vision did your instructor drag race in the early eighties in NHRA G/MP or H/MP. Those cars had to weigh 12.00 to 14.00 lbs per CI. They were a driveshaft makers nightmare. Ring and pinions were turned into crushed ice. I remember destroked 302s about 272ci @750hp, dropping the clutch at 10,000 rpms at 3600 lbs. You would just hold your breath watching them grab second gear so the front end would not come crashing down. You brought back some old but good memories.
Lou
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  #27 (permalink)  
Old 05-11-2010, 09:11 PM
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HP is a power measurement, torque is an effort measurement. You can't make comparisons between these two measurements other than the simple mathematical relationship between the two.

Why people insist on comparing the two as if one was better than the other is beyond me.
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  #28 (permalink)  
Old 05-11-2010, 09:54 PM
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HP = Torque x RPM 5252

Where the argument? With out torque you have no HP.
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Old 05-11-2010, 10:54 PM
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X2

X2, AP, I'm not sure where you're going with this. If you think that you've stumbled on to something that is contrary to current physics, maybe you're looking at old vs. new engine design and seeing a difference. Old school worked at making lots of torque or lots of horsepower. New technology has moved towards making more average power across the RPM band resulting in some Kansas flat torque-horsepower bands that get alot of work done. With proper gear selection these modern engines can result in faster ET's than some of the torque or horsepower monsters of the past. The science is still the same, if you take ANY torque out of the equation, you get a lower horsepower as a result at a given RPM level. This is not new science, its about modern engineering design. I hope this helps you in your quest toward better understanding of automotive technology. I think that some of your posts mislead the younger members cause you get a bit off base sometimes, but at least you're thinking. olnolan
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  #30 (permalink)  
Old 05-12-2010, 12:08 AM
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Well I'm going to make this really simple for you.


All things being equal

The more torque you have the faster you will get to your top speed.

The higher you can rev (continue accelerating) the higher your top speed.

Now the 1/4 mile you have to hit the highest top speed you can and get there as quick as possible. There is kind of an optimum point for any car making any amount of power.

What you need to look at in the 1/4 mile is what is happening at the rear wheels

If you have a 3000 lbs car with 600 ft lbs of torque and 500 hp would it beat an identical car with 400ft lbs of tq and 700 hp.

Your answer, it depends on the final overall gear ratio. If you have a large mechanical advantage the car with less tourque is going to be more properly balanced in regards to acceleration vs top speed. The car with the torque will get up to speed really quick (if it has traction) but will rev out and not be able to hit a very high top speed.

Now if the overall gear ratio offers a low mechanical advantage, the car with tons of torque will power ahead to a high top speed, while the car with lots of HP and no torque will slowly chug up to speed and never hit its top speed before the finish line.


If you haven't figured it out this is the challenge of building a car for the 1/4 mile. Find the right setup, engine, transmission, rear gears, tire size, to get you to the optimum top speed before the finish line. There is no torque wins or HP wins.

If you could afford it I would build a high HP car with a 327 and a high TQ car with a 454 against anything you built and I could be pretty certain that unless you get a clue real quick both my cars would beat yours hands down any time. On top of that these "blind old men" on this message board would spank me and you every time with half the money into their car because of all heresay that is rattling around in their brains.




The thing that amazes me the most is all the members in it including myself took the time to post despite the fact that "YOU KNOW IT ALL". I work with a guy like you, its a shame everyone wants him promoted so we don't have to listen to him ask questions to the guys who have been working there for 30 years just so he can tell them how things really work.

I'm going to sign back out and continue reading on here so I can learn from some very knowledgable people and from the problems they are having with their REAL PROBLEMS not their FANTASYLAND THEORIES.
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