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Had my 2012 5.0 Dyno'd today, best was 386.40/373.45, SAE, 5th gear (1:1), 93 octane Sunoco, 3.73's (Stock)

 

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Strong numbers !
Mine made 388 rwhp & 377 ft lb with just axle back exhaust on a Dynojet.

Congrats
 

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Awesome numbers! Can't wait to get mine.
 

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Wow 386 stock!? What is that (roughly) at the flywheel? I'm thinking like 450...that's quite impressive if that's right.
 

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MTs have shown around a 10-12% drivetrain loss, so splitting the difference gives around 433 at the crank.
 

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MTs have shown around a 10-12% drivetrain loss, so splitting the difference gives around 433 at the crank.
Ok that makes more sense. I guess I was thinking it was 15-18% but that's probably for automatics. Still damn good numbers!
 

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Actually I am told the automatics loose less HP then the manuals these days.
 
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Actually I am told the automatics loose less HP then the manuals these days.
Automatics will always draw more power from an engine than a manual trans due to the increased number of gearsets including planetary gears, as well as the torque converter itself and sheer volume of fluid.

That being said, attempting to calculate drivetrain loss through arbitrary percentages is a waste of time. You can make up any number you want but until you actually pull the engine and put it on a dyno you will never know what it is putting out at the flywheel.
 

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Actually I am told the automatics loose less HP then the manuals these days.
You are told wrong. A fluid coupling (torque converter) will always always always absorb more power than a direct mechanical coupling (clutch). That having been said, most torque converters have lockup clutches that eliminate this loss, but they only engage at certain speeds.

Furthermore, at every junction between two surfaces, energy is lost. Manuals have one - the interaction between the input gear and the output gear. Automatics can have as many as 5 or 6, depending on what gear you're in. All those clutch packs and planetary gear sets soak up power.

The Mustang drivetrain absorbs less power than most other vehicles because it has a solid rear axle. CV joints soak up a lot of power, and the Mustang has none (well, one in the driveshaft, but that's a little different). Most vehicles have at least 4 - 2 in each CV axle.

Very generally speaking, most manual-equipped cars will lose 15-17%, and most auto cars will lose 17-22% (a lot depends on how efficient the auto is). AWD vehicles will lose 25%+. The Mustang in manual configuration will generally lose 10-12% (remember, solid rear end transmits more powah), and the autos lose 15-17%. As always, YMMV. Drivetrain clearances play a huge part - if the clearances on your car are bigger, you'll lose more power.

Most MT 5.0s will dyno in the 360-380 range, while 350-370 is considered average for an AT 5.0. Of course, this doesn't include torque multiplication from the torque converter, or the greater repeatability on the strip, both of which make the AT the preferred car for serious strip junkies.
 

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