What is "peak power" & "power under the curve"?
10-13-2013, 12:29 PM
#1
What is "peak power" & "power under the curve"? Before you guys start saying "
"...i'd like to let you know that i DID do a search...on google and here but i couldnt find anything that explained it. So i gave up and here i am, asking here.
I keep on hearing power under the curve and peak power when it comes to FI and i have no idea what it means. I first came across the terms when i asked what the difference between supercharger and turbocharger was.
So in layman's terms...what does it mean? I'm new to FI so plz keep that in mind when answering. It would be really nice if anyone could explain the practical difference...like how it feels behind the wheel. Thanks a mil in advance guys!
"...i'd like to let you know that i DID do a search...on google and here but i couldnt find anything that explained it. So i gave up and here i am, asking here. I keep on hearing power under the curve and peak power when it comes to FI and i have no idea what it means. I first came across the terms when i asked what the difference between supercharger and turbocharger was.
So in layman's terms...what does it mean? I'm new to FI so plz keep that in mind when answering. It would be really nice if anyone could explain the practical difference...like how it feels behind the wheel. Thanks a mil in advance guys!
10-13-2013, 01:12 PM
#3
They are literally what they sound like.
Peak power is the highest number.
Power under the curve refers to how broad the powerband is. If a car makes 200 HP from 3000 to 6000 rpm and then jumps to 700 HP at 7000 rpm, it doesn't have a very broad curve, and poor power below the curve. If a car made 400 HP at 3000 rpm and continued up to 600 HP by 6500 rpm, it would have a much broader powerband and more area under the curve. Generally, a car with more area under the curve will outperform a car with a higher peak HP number hut with less power below the curve.
Peak power is the highest number.
Power under the curve refers to how broad the powerband is. If a car makes 200 HP from 3000 to 6000 rpm and then jumps to 700 HP at 7000 rpm, it doesn't have a very broad curve, and poor power below the curve. If a car made 400 HP at 3000 rpm and continued up to 600 HP by 6500 rpm, it would have a much broader powerband and more area under the curve. Generally, a car with more area under the curve will outperform a car with a higher peak HP number hut with less power below the curve.
10-13-2013, 01:13 PM
#4
Having good power under the curve means power at lower rpms. Peak power is pretty self explanatory.
Let's say you put a giant 114mm turbo on a small engine. It would spool late, but make 10000000 hp wayyyyy up in the rpm band. So the owner of that terrible combo would be telling their tuner/builder that their car lacks power under the curve.
Let's say you put a giant 114mm turbo on a small engine. It would spool late, but make 10000000 hp wayyyyy up in the rpm band. So the owner of that terrible combo would be telling their tuner/builder that their car lacks power under the curve.
10-14-2013, 02:40 AM
#6
TECH Veteran
iTrader: (12)
Join Date: Dec 2004
Location: Rockville, MD
Posts: 4,354
Likes: 0
Received 0 Likes
on
0 Posts
your power 'under the curve' is really what makes the car go and do what the numbers say it should. peak is a number that is for dick waving and inflating avg power numbers.
more technically speaking.. power under the curve is also how the power is metered by the engine itself. large amounts of power under the curve dont hit as hard but pull for what feels like forever. they can actually be easier on the car to a point. being able to put power down more gradually is a good thing for various types of racing.
while peaky cars (supras, big turbo 4cylinders, etc) ted to hit hard and can be insanely hard on the car making it potentially tougher to get out of turns or keep a car hooked up at the strip. ODR cars and other turbo drag cars build boost and meter it out in such a way that i would bet makes the power curve look much flatter (more under the curve) than a dick waving dyno run.
sometimes.. power under the curve is also referred to as 'usable' power.
more technically speaking.. power under the curve is also how the power is metered by the engine itself. large amounts of power under the curve dont hit as hard but pull for what feels like forever. they can actually be easier on the car to a point. being able to put power down more gradually is a good thing for various types of racing.
while peaky cars (supras, big turbo 4cylinders, etc) ted to hit hard and can be insanely hard on the car making it potentially tougher to get out of turns or keep a car hooked up at the strip. ODR cars and other turbo drag cars build boost and meter it out in such a way that i would bet makes the power curve look much flatter (more under the curve) than a dick waving dyno run.
sometimes.. power under the curve is also referred to as 'usable' power.