[SS 1LE]

So took the car out tonight and did a handful of short pulls. Did high rpm (5500-6000) 1-2 and 2-3 shifts. Car pulls great, but this exhaust noise kinda annoys and baffles me with it's randomness. Like on maybe half of those 1-2 shifts I would get the noise I was talking about, what I would describe as a single, loud pop/backfire/gunshot sound just as I come off the gas to shift. I see some say this is clutch fuel cut off CFCO, which makes sense, but why doesn't it always do it? And I thought that was only for no lift shift? It's kinda loud and annoying when it does it, like it makes you think your tunes wack. I've owned multiple manuals, with even more open exhausts, none did anything quite like this. Not sure I like it very much at this point...but I guess a tune is the only way to remove this? Don't have any desire to do that at this time...guess I'll have to just get used to it.

[Brewmaster]

My A8 does it reliably, but it pretty much has to be floored and it will pop in between gears. I agree with others, it is intentional - same type fuel management tricks that other euro car compainies do to make their v8's sound and look cool. I bought the car partially because of how bad ass it sounds! Problem is sometimes not enough room to wind this thing out, I try to get one pop on the way home every day - it's like therapy!

[SS 1LE]

Originally Posted by Brewmaster

My A8 does it reliably, but it pretty much has to be floored and it will pop in between gears. I agree with others, it is intentional - same type fuel management tricks that other euro car compainies do to make their v8's sound and look cool. I bought the car partially because of how bad ass it sounds! Problem is sometimes not enough room to wind this thing out, I try to get one pop on the way home every day - it's like therapy!

On my car it's more than just a pop to my ears though, it sounds like a pretty loud, single gunshot sound...

[LibertyHill]

Originally Posted by SS 1LE

On my car it's more than just a pop to my ears though, it sounds like a pretty loud, single gunshot sound...

Thats as good as it gets. You aced it!

Reminds me of turning the ignition off for for a few secs and then back on as a kid when passing somebody walking along a backroad.

[bybcous]

Originally Posted by SS 1LE

On my car it's more than just a pop to my ears though, it sounds like a pretty loud, single gunshot sound...

Mine too sounds like a gun shot, i always look around and see if people think someone is shooting.

[thescout6]

Originally Posted by SS 1LE

Thought I read similar, but for the autos?

Thing is it doesn't always do it, high rpm 1-2 shift if I do it say five times, maybe it will do it once or twice.

It must have a small window of circumstances that must be met for it to happen is my guess.

Definitely happens on the Autos. It's the fuel cut off backfire at shift that cause the pop. In an A8 with pedal to the floor the yell of the NPP and the pop when it shifts is like a the best woody I've ever gotten haha. Sounds like flames spitting out like they did in my old EvoX


Sent from my iPhone using Tapatalk

[crankaholic]

@SS 1LE try to do a no-lift shift... keep your right foot planted as you shift quickly near redline. It takes a bit of mental gymnastics at first, because you're so used to lifting, but you'll see what we're all talking about. The car will cut spark and RPMs will drop very quickly to where they need to be for the next gear (accompanied by that awesome backfire). Yes it does sound like a gunshot and it's pretty rad

[SS 1LE]

Originally Posted by crankaholic

@SS 1LE try to do a no-lift shift... keep your right foot planted as you shift quickly near redline. It takes a bit of mental gymnastics at first, because you're so used to lifting, but you'll see what we're all talking about. The car will cut spark and RPMs will drop very quickly to where they need to be for the next gear (accompanied by that awesome backfire). Yes it does sound like a gunshot and it's pretty rad

Yeah, I'll give that a go soon. But like I said, my car does that gunshot sound at times on a high rpm, quick, 1-2 shift, even when NOT using no lift shift. This is what surprises me? Does yours?

[crankaholic]

Originally Posted by SS 1LE

Yeah, I'll give that a go soon. But like I said, my car does that gunshot sound at times on a high rpm, quick, 1-2 shift, even when NOT using no lift shift. This is what surprises me? Does yours?

Yes, it's because you start lifting off the gas a fraction of a second after you touch the clutch... by that point the ECU thinks you're trying to do a no lift shift and does it's thing. I trained myself to do that all the time, I still lift because I think it's easier on the drivetrain to re-engage without instant power, but the spark cut helps drop the RPM faster and produce a smoother shift.

[SS 1LE]

Originally Posted by crankaholic

Yes, it's because you start lifting off the gas a fraction of a second after you touch the clutch... by that point the ECU thinks you're trying to do a no lift shift and does it's thing. I trained myself to do that all the time, I still lift because I think it's easier on the drivetrain to re-engage without instant power, but the spark cut helps drop the RPM faster and produce a smoother shift.

Oh, so the no lift shift is that sensitive? I assumed it needed full clutch engagement, not just a small touch. But, that could explain why sometimes I get the gunshot sound and other times I don't. I guess sometimes I am touching the clutch before backing off the throttle...am I interpreting you correctly?

Thanks!

[crankaholic]

Originally Posted by SS 1LE

Oh, so the no lift shift is that sensitive? I assumed it needed full clutch engagement, not just a small touch. But, that could explain why sometimes I get the gunshot sound and other times I don't. I guess sometimes I am touching the clutch before backing off the throttle...am I interpreting you correctly?

Thanks!

Yeah, that's what seems to be happening. It has to be that sensitive, to have enough time to bring RPMs down for a quick shift and not rev the engine further as you're disengaging the clutch.

[SS 1LE]

Originally Posted by crankaholic

Yeah, that's what seems to be happening. It has to be that sensitive, to have enough time to bring RPMs down for a quick shift and not rev the engine further as you're disengaging the clutch.

Makes sense.

So as a practice you don't do a full on no lift shift, you just make sure you touch the clutch before you lift so you "partially" use no lift shift? And this will give you the loud gunshot like sound when doing a high rpm shift?

Do you ever get the gunshot like sound when you do the same procedure on a 2-3 shift, or just on the 1-2 shift?

I appreciate the feedback bud.

[crankaholic]

Originally Posted by SS 1LE

Makes sense.

So as a practice you don't do a full on no lift shift, you just make sure you touch the clutch before you lift so you "partially" use no lift shift? And this will give you the loud gunshot like sound when doing a high rpm shift?

Do you ever get the gunshot like sound when you do the same procedure on a 2-3 shift, or just on the 1-2 shift?

I appreciate the feedback bud.

No problem. I do it for every high RPM shift... well this thing is so fast that I've only shifted at the top of 3rd (would love to lower the rear-end ratio for more fun... but that's another topic). GM did program no lift shift into the car and I do use it occasionally, but I don't want to put more stress on the drivetrain than necessary so I just enjoy the sound while actually granny shifting

To answer your question, the car should no lift shift into every gear.

[SLVR17]

Mine tends to do it on cold morning starts. and definitely as I'm shifting and letting go of the gas. It reminds of my old sti I used to make it backfire on command. All it really is. Is a rich fuel mixture being cut of as you lift off the throttle. I leave for work at 5am. So I'm sure the neighbors hate me. But they are they drive mustangs so it's ok