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Ok so I am in paddle shift mode in my 392 Hemi Challenger, holding 1st gear at about 2500 rpms....and nail the throttle to the floor coming out fishtailing...as I hit 6500 rpms, I paddle shift to 2nd...3rd etc...My question is this. If I hold the pedal to the metal, there is a hesitation or burp between shift and acceleration to the next level. Almost like a flooding of fuel and subsequent misfire results. Is this normal? If with a clutch, I would of course let up on the gas between shifts...I wasnt sure I needed to do that in paddle mode...any feedback? Thanks!
 

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I have that on some upshifts in the lower gears too. Noticed it first while going for 0-60 runs. I've ignored it because when not on it I drive like a granny (too many tickets) so I blamed it on my adaptives. But if it's something else I'd like to know. Mine is an R/T, by the way.
 

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My R/T auto does the same.

Didn't notice with stock exhaust. Very obvious with Borla ATAK.

Just accelerating hard in auto mode didn't have the same "burp" effect. But when using the paddle shifters and shifting under hard acceleration, at high revs, there was a definite "burp" that passengers even commented on.
 

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Ok so I am in paddle shift mode in my 392 Hemi Challenger, holding 1st gear at about 2500 rpms....and nail the throttle to the floor coming out fishtailing...as I hit 6500 rpms, I paddle shift to 2nd...3rd etc...My question is this. If I hold the pedal to the metal, there is a hesitation or burp between shift and acceleration to the next level. Almost like a flooding of fuel and subsequent misfire results. Is this normal? If with a clutch, I would of course let up on the gas between shifts...I wasnt sure I needed to do that in paddle mode...any feedback? Thanks!
@ 6500 RPM, you're hitting the rev limiter. Shift it at less than 6400 RPM and you will notice a slight puke which is the tq mgmnt pulling air and fuel. Get a custom tune to remove tq mgmnt and grin ear to ear while shifting at 6500 RPM.
 

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Its likely torque management as the transmission engages the clutches for the upshift.

At that rpm, you might be hitting the rev limiter, which will cut fuel and ignition until you fall below the limiter's threshold. IIRC, the OEM limiter is 6450 rpm on the 6.4.
 

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I thought the Auto in stick mode would automatically upshift BEFORE you hit the rev limiter? Isn't it designed to do that? That is why the 1/4 mile guys recommend putting it into 1st and leaving it alone while you fly down the track. No?
 

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Here is what tq mgmnt looks like on a log.
So you are talking about the momentary loss in power as the car switches gears. That I can understand, and maybe that is the question the OP had.

I read his concern through my own lens, where the car makes a huge, loud, and angry burp when I was upshifting at high revs, under hard acceleration, but not at the rev limiter. The momentary power dip as the new gear was engaged and the revs dropped was expected, but the angry sound that came from the exhaust was not.

Perhaps we are talking about different things here. I'll wait and see if the OP responds and makes it clear.
 

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I thought the Auto in stick mode would automatically upshift BEFORE you hit the rev limiter? Isn't it designed to do that? That is why the 1/4 mile guys recommend putting it into 1st and leaving it alone while you fly down the track. No?
Mine does it during AutoStick runs on the 1-2 and 2-3 shifts as I let the tranny do the shifting at WOT, and it does it too when I'm shifting myself, which is before redline and limiter. I couldn't tell you the exact RPM because I drive with the seat of my pants, especially since I can't read the tachometer. In Drive the lull is a lot smoother, like a manual shift feels, while in AutoStick it does feel like a burp or a puke. Good to know it's just torque management.
 

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Exactly! It is the momentary loss of power as the motor "pukes" air. Sounds like it is coming from engine, not exhaust. Thanks for all the feedback! Just wanted to make sure it wasn't a tune issue or something else wrong with car. It does not do it in auto mode.
 

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My old Charger had come (used) with a K&N filter and with the windows down I could hear that thing like gasp for air between shifts; it was a riot! At least some of the sound is from the intake.
 

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Try shifting with traction control off.....Bye Bye Burp! :)

I can redline it and shift with no burp at all with it off.....but be warned, you will fish tail a bit from 1st to 2nd and then again to 3rd. Puts a smile on my face......
 

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If your running the stock tune, tq mgmnt happens at shift to help protect the drive train. It happens fast (milliseconds) but it is substantial enough to push your head forward a little. It closes the throttle body plate a little which may be changing the air intake enough to cause a change in sound. It also pulls up to 10 degrees of timing (again only for milliseconds and only at shift).
Here is the same log but with the actual spark cycl #1. You can see the timing spike down at shift.
Tq mgmnt can happen at 3/4 throttle or WOT. I don't know what triggers the ECU to activate tq mgmnt but my guess would be a high enough MAP signal voltage along with an input from the TCM. I guess the lateral G Force sensor may be able to trigger it as well (if you started to get the car bass ackwards).
Either way, Tq mgmnt removal is the most beneficial part of a tune. Especially in the A5s. It is worth .3 seconds in the 1/4. A5s gain more from the tq mgmnt reduction than any power gains from the tune.
In sport mode, it will not auto upshift in paddle mode (2012). It will bounce off the rev limiter. It will upsift in "D" and sport mode and that is usually the quickest. A tune with raised rev limiter and raised shift points really helps in hitting the next gear hard and at a better RPM for greater pull.
 

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Try shifting with traction control off.....Bye Bye Burp! :)
I always have TC and ESP off and my car still burps. This doesn't remove torque management; a tune is needed for that.
 

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My '13 does this as well, and frequently barks the tires hitting 2nd. Love it!
 

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with ESP off does it still burp as bad?
The only times when I have ESP on is when I forget to turn it off, which is not often. All I can tell you is that the hesitation/burp/hiccup/puke is very noticeable in the middle of a WOT run. Feels like you hit the brakes or the fuel was cut off for a split second. ESP off doesn't remove torque management so I think it should be the same.
 

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TC & tq mgmnt are two different things but they do interact. By turning off TC, the rear brakes will not grab when slippage is detected. So with TC partially off or fully off, it will still pull timing, fuel and air at shift but it may not be as noticeable. Tq Mgmnt can only be reduced with a tune (canned or custom).
 

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I always have TC and ESP off and my car still burps. This doesn't remove torque management; a tune is needed for that.
I am very surprised that it doesn't work for you. I had a huge burp before I tried turning TC off, now I don't even feel it. I just went for a ride and redline shifted several times and there was no hesitation at all. It feels like a seamless shift from 2nd to 3rd...almost instantaneous if you will...perfect in my book. I guess it all depends on what your running maybe?
 

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TC & tq mgmnt are two different things but they do interact. By turning off TC, the rear brakes will not grab when slippage is detected. So with TC partially off or fully off, it will still pull timing, fuel and air at shift but it may not be as noticeable. Tq Mgmnt can only be reduced with a tune (canned or custom).
I agree completely. The difference for my car with it on or off though is night and day. I had a huge belch before but now with it off, it's 99.5% gone. Works for me.
 
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