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Old 11-20-2012, 09:17 PM
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Default could someone explain

what "under the curve" means?

been trying to figure it out but... be easier if someone just told me.
Old 11-20-2012, 11:04 PM
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Usually when people say this, they are referring to power/torque in the rpm range under peak. It's an important consideration, since most street setups won't spend much time at their actual peak. Average power/torque across your usable rpm range will be a better indicator of overall road feel/performance for a street setup, rather than looking at peak numbers alone.
Old 11-21-2012, 01:27 AM
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i understand what you're saying about hp/tq in rpm range before peak but i guess i'm still not 100% on how it is achieved. can someone give an example of a set-up that stays "under the curve" or an example of some kind to better comprehend. i'm just not getting it
Old 11-21-2012, 01:51 AM
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what it means is a less steep graph...

if you make 80% of your peak HP by 4k rpm's then your making alot of power under the curve...
Old 11-21-2012, 02:07 AM
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Look at a dyno graph. "The curve" is mainly refering to the highest point of peak power on the graph. The more space under that line the more power to be had. It means that your peak power is made early 3-4,000 rpms and holds it till 6500-7000rpms. Less power under the curve means the line peaks later 4000-5000rpms and holds till 6500-7000.
Old 11-21-2012, 02:11 AM
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A 228R cam coupled with PRC 5.3 3.5 heads and an ls6 intake would make excellent power under the curve...
An Ms4 cam coupled with hogged out ls6 heads and a ported FAST 92/92 would make excellent peak but be "sluggish" compared to the 228R setup under 4K RPMs.

This is taken into way more consideration with M6 guys, that can actually "use" power in a modified car at 2500-3500RPMs. Most people with a 4000 converter could care less about how a car "feels" at 3000RPMs taking off next to mini vans.
Old 11-21-2012, 05:50 PM
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ohhh, i get it now... hence, "its not how fast you can go, but how fast you get there"

so basically, at an RPM (ex: 3200), hp/tq start their incline(on a graph) and increase to its peak at, ideally, a shift point.. and if thats correct, in this example, would a 3200 stall be recommended?
Old 12-04-2012, 10:38 PM
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I always understood it as "area under the curve". Some cars make crazy power but peak at 7500+ rpm so they really aren't fun on the street. Most guys want more area under the curve which means a higher average HP instead of a high peak HP. If you could compare 2 graphs and measure the area under the HP line.. the faster car should have a greater area which translates to higher average HP.



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