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Old 03-27-2011, 03:55 AM   #1
Swervin309
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Default Lumpy Torque Curve. Normal?

I did a dyno run after flashing a new tune (Brenspeed) that was updated for the new mods. Numbers were 291 @ 5400/308 @ 4400 (275/294 previously). I noticed that the torque curve was rather lumpy and would spike and flatten for a few hundred RPM. Is this normal? Tuning? Or am I retarded? Thanks guys.
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Old 03-27-2011, 04:11 AM   #2
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what are your mods?

LT's with cat delete? if so, ensure the rear O2's are turned off
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Old 03-27-2011, 04:13 AM   #3
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BBK CAI, BBK 62mm TB, Shorties, Dynomax Ultra-Flo Welded muffs, 91 tune.
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Old 03-27-2011, 01:04 PM   #4
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Check for air leaks on your Cai and TB. That can cause wierd spikes


Not bad numbers otherwise for relatively unmodded. How was your A/F ratio?
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Old 03-27-2011, 01:15 PM   #5
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Quote:
Originally Posted by Tylus View Post
Check for air leaks on your Cai and TB. That can cause wierd spikes
No leaks. I checked everything before I pulled.


Quote:
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How was your A/F ratio?
Not sure. I haven't put a wideband on it yet. Although she did like being "2% richer".
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Old 03-27-2011, 01:16 PM   #6
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No it's not normal at all. Your torque and HP curves along with your AF ration should be as smooth as possible.
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Old 03-27-2011, 01:22 PM   #7
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Old 03-27-2011, 04:22 PM   #8
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Is this an automatic?

From the looks of the run I would say something off on the dyno.

What did the shop say?
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Old 03-27-2011, 05:13 PM   #9
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Nah, it's a 5.

The shop didn't say anything other than "Your HP curve looks smooth". I gives a s*** about HP.
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Old 03-28-2011, 11:36 AM   #10
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I torque curve like that would be felt by the driver and probably heard from those listening. Point to the spot on the graph and say WTF? What is that? Make them explain.
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