HP vs. Trq

Old 06-07-2011, 03:23 PM
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HP vs. Trq

We all know the F20/F22C engines in the S rev like crazy and produce some of the highest specific output of any engines out there.

We also know it's torque that moves the car. So, why rev the engine past it's peak torque output (F22C 162 ft lbs @ 6800 rpm, F20 153 ft lbs @ 7500 rpm) ???

Other than producing noise, what else am I getting for the extra 1000 or so revs? Anyone care to comment??

I'm curious......
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Old 06-07-2011, 03:29 PM
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torque isnt what moves the car.

torque applied over time is what moves the car.

torque applied over time is called horsepower.

/thread
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Old 06-07-2011, 03:53 PM
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Originally Posted by Glenn1 View Post
So, why rev the engine past it's peak torque output
Because revving it up is just way too much fun to stop prematurely.

Last edited by Silverstone_Ryan; 06-07-2011 at 03:57 PM.
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Old 06-07-2011, 03:56 PM
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Originally Posted by Silverstone_Ryan View Post
Because it's just way too much fun to stop prematurely.
that's what she said!
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Old 06-07-2011, 03:59 PM
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Nice, Ryan. Yeah, T6, I know the definition of hp......just wanted to know if there's any benefit, other than aural, in revving to redline.
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Old 06-07-2011, 04:05 PM
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Originally Posted by Glenn1 View Post
Nice, Ryan. Yeah, T6, I know the definition of hp......just wanted to know if there's any benefit, other than aural, in revving to redline.


Seriously, I think the most important reason to rev it all the way out is so that you can stay in the most powerful part of the powerband. The peak torque may be at 7500rpm but if you shifted at 7500rpm you'd drop down below VTEC. So you rev it all the way up so you can stay in the powerband by overlapping the peak of 7500rpm on either side with your shifts.
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Old 06-07-2011, 04:05 PM
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Originally Posted by Glenn1 View Post
Nice, Ryan. Yeah, T6, I know the definition of hp......just wanted to know if there's any benefit, other than aural, in revving to redline.
i thought i explained it. more horsepower = more work can be done.
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Old 06-07-2011, 04:15 PM
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Originally Posted by Silverstone_Ryan View Post
Because revving it up is just way too much fun to stop prematurely.
I find the most fun is hitting apexes at 60 mph or above and accellerating throughb the turn to + 30 mph not maximum speed.

Jonathan
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Old 06-07-2011, 04:34 PM
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I created this chart using the torque curve for an AP1 (stock). The vertical scale represents torque multiplied by gear ratios. The horizontal scale represents speed (stock gears). If you want to know what benefit the torque past the peak provides just look at the gap between the lines. When you get into higher gear, shift where they intersect.
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Old 06-07-2011, 04:38 PM
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Lower gearing is a torque multiplier, while peak torque is at a lower RPM the torque curve of the S2000 is fairly flat with a bump up at VTEC, and then still fairly flat. The longer you stay in the lower gear, the longer you benefit from the torque multiplying effect of that gear ratio.

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Old 06-07-2011, 06:00 PM
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The equation for horsepower is = (TQ * RPM)/5252

You need RPM AND torque to make power. Notice how the hp and torque curves cross at 5252 RPM on every dyno graph.

ONLY torque is measured from the dynamometer, hp is calculated.
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Old 06-08-2011, 01:26 PM
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Originally Posted by rattpak View Post
I created this chart using the torque curve for an AP1 (stock). The vertical scale represents torque multiplied by gear ratios. The horizontal scale represents speed (stock gears). If you want to know what benefit the torque past the peak provides just look at the gap between the lines. When you get into higher gear, shift where they intersect.
Awesome visual representation of the answer. Sometimes a picture tells the story best.
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Old 06-08-2011, 09:56 PM
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Originally Posted by TheCarGuy2021 View Post
The equation for horsepower is = (TQ * RPM)/5252

You need RPM AND torque to make power. Notice how the hp and torque curves cross at 5252 RPM on every dyno graph.

ONLY torque is measured from the dynamometer, hp is calculated.
pretty much what I was going to say. People will argue about what matters more but truthfully they are all equal. Torque is the actual force the engine is putting out. RPM is how fast the engine is turning that force. HP is just a number to measure the output.

There are so many more factors to automotive performance than just horsepower and torque. But people are obsessed with these numbers. RPM and gearing are just as important.

You could have an engine that produces 1000 torque but if it redlines at only 1k rpm then you have to have some really long gearing to take advantage of that. Our S on the other hand has only a bit of torque but revs really high so it can have really short gearing.

Someone correct me if im wrong but according to my math the true final drive reduction on our cars is 4.75 on the AP1 and 4.95 on the AP2.
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Old 06-10-2011, 03:26 PM
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That is correct if you are including the secondary reduction performed in the transmission.
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Old 06-10-2011, 08:31 PM
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I am Thanks for the input
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Old 06-10-2011, 09:10 PM
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Originally Posted by 0tyrael0 View Post
pretty much what I was going to say. People will argue about what matters more but truthfully they are all equal. Torque is the actual force the engine is putting out. RPM is how fast the engine is turning that force. HP is just a number to measure the output.

There are so many more factors to automotive performance than just horsepower and torque. But people are obsessed with these numbers. RPM and gearing are just as important.

You could have an engine that produces 1000 torque but if it redlines at only 1k rpm then you have to have some really long gearing to take advantage of that. Our S on the other hand has only a bit of torque but revs really high so it can have really short gearing.

Someone correct me if im wrong but according to my math the true final drive reduction on our cars is 4.75 on the AP1 and 4.95 on the AP2.


lets say you can move 100lbs of stuff 500 times in 1 minute.
someone else can move 50lbs of stuff 1000 times in 1 minute.

in this case both are equal.

now lets say its 200lbs 5000 times in 1 minute.
and the other is 140lbs 9000 times in 1 minute, then the 140 is greater.

Now this is a crappy example and not exactly how it works, but i'm sure you get the idea.
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Old 06-10-2011, 09:43 PM
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Originally Posted by CLOS View Post


lets say you can move 100lbs of stuff 500 times in 1 minute.
someone else can move 50lbs of stuff 1000 times in 1 minute.

in this case both are equal.

now lets say its 200lbs 5000 times in 1 minute.
and the other is 140lbs 9000 times in 1 minute, then the 140 is greater.

Now this is a crappy example and not exactly how it works, but i'm sure you get the idea.
Yep thats a good way of putting it too
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