4.6L (1996-2004 Modular) Mustang Technical discussions on 1996-2004 4.6 Liter Modular Motors (2V and 4V) within.

What's going on with my torque curve? (Dyno pic)

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Old 04-11-2011, 11:01 PM
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Ultrashock
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Default What's going on with my torque curve? (Dyno pic)

Dyno read 266/295.

96 cobra
CAI
Full exhaust
UDP
Tune by Murillo
3.73 (maybe)


Just wondering why the torque falls like that.

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Old 04-11-2011, 11:14 PM
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Bmitchell373
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ur a/f ratio dropped a bit, so could be in the tune.
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Old 04-11-2011, 11:17 PM
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Ultrashock
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AF was at 13 nearly straight through. Why would it have a steep drop off?
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Old 04-12-2011, 07:17 AM
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mrtstang
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What's weird to me is how your torque seems to fluctuate but not the horsepower.
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Old 04-12-2011, 07:29 AM
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WhiteFoxGT
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Well first off I cant see where it dipped RPM wise, but if I were to guess it would be the IMRC's opening. You lose torque with them open low in the revs but you will build power. Which is why the torque dipped and the HP kept climbing

Last edited by WhiteFoxGT; 04-12-2011 at 07:35 AM.
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Old 04-12-2011, 07:31 AM
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WhiteFoxGT
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And BTW that is 1 weird *** dyno sheet. Heres ones Im used to looking at (my old Lightning) Only thing I wish was different on the layout was speed at the bottom needs to read rpm

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Old 04-12-2011, 11:07 AM
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Ultrashock
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Sorry for the crappy picture. I'd scan it but the drivers for the printer are all screwed up.

I mean, I really trust Murillo as he's one of the best tuners around. It just looks odd and everyone I show says the same thing. Maybe weird is good.

The torque starts to fall at around 4k RPMs. The HP peaks at around 5k and holds through 6k.

Maybe it's in the tune. Just enough torque to push the car into the higher rpms where the 4vs build power? Any other suggestions?

Also this was PowerDyne. Upper 80's low 90's with back to back pulls.
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Old 04-12-2011, 11:15 AM
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Moonshine
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Man your tq is so much higher than mine... I was running a pretty terrible DS canned tune. Wonder if I'll peak higher #'s with the SCT.

My tq was actually WAAAAYY different. I'll show a pic later. Seem PB is updating or something.
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Old 04-12-2011, 11:53 AM
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Ultrashock
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Originally Posted by Moonshine
Man your tq is so much higher than mine... I was running a pretty terrible DS canned tune. Wonder if I'll peak higher #'s with the SCT.

My tq was actually WAAAAYY different. I'll show a pic later. Seem PB is updating or something.
What's PB?

Also, yeah canned tunes suck. Maybe go with something from BAMA or Brenspeed. STC is the way to go man. I was talking to a guy up there and since the Cobra motors are hand assembled, there's not as much variation from car to car (factory freaks). Although, I would always recommend a dyno tune.

Oh and if you want to pass emissions, have them write you up a 'emissions tune' or have it show up N/A on the readiness checker. Failed, had Murillo create a special tune, and passed.
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Old 04-12-2011, 12:16 PM
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WhiteFoxGT
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Do you understand how IMRCs and the variable intake runner length effects torque? Thats my only guess as to what your sheet says. Also, it looks like a dramatic decrease becuase of how the numbers are scaled. If it was by 50-100 intervals, it wouldnt look so steep
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