Hey gents, lots of good information regarding this. If I have a stock A8 c7z06 and would like some burbles (not as much as alessio) should I consider swapping to borla xpipe as well? Also would just the tuner device be suffice on a stock car to create this beautiful sound
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Last edited by mtb703; 07-08-2020 at 09:39 AM.
Not a lot of reason to try and get more burbles on the stock exhaust setup with 4 cats. They will pretty much drown it out. You at least need a secondary cat delete.
There is no need to change DFCO at all. The safe way to set this up is to allow the much lower spark advance as you lift throttle and the car transitions into DFCO. This way you will get plenty or burbles for a few seconds. If you have headers and high flow cats you can turn it into snaps crackles and pops as it transitions and it will sound great. Now if you have NO CATS, you can disable DFCO and the car will endlessly crack and pop rather obnoxiously on decel. It will burn up extra fuel and in my opinion be incredibly annoying. If you disable DFCO and you have CATs, you will shorten their life at minimum and you could even destroy them with the excessive non stop pops.
IMO, it sounds best by lowering the base spark between 2000-3600 columns and leaving DFCO alone. This way you will not have weird burbles in the parking lot at low speeds and you wont have needlessly low timing when cruising and letting off the throttle where pops are not created anyhow, just low low timing and hot exhaust heating up the cats. But you will have wonderful pops and crackles on throttle blips, rev match down shifts(manual), and paddle downshifts(auto).
I messed with the min spark tables and the main spark tables started at 10 and went all the way down to -10 and got no pops on my C7 Z06. I can see the timing drop on decel but almost sounds like there is no fuel to ignite it. I tried disabling dfco but no change. I still have all four cats. Stock A8 cars burble/pop on downshifts and so do ZR1 stock, so I feel like I should still be hearing some pops? I've done this on a number of different cars and never had a problem getting pops, not sure why this car won't do it. My C6 Z06 would pop good at 10 on decel but had full catless headers. I'm waiting on my catless xpipe to come in and hoping it's just that extra muffling. I also posted a thread on it if you have any insight.
Mine popped with cats no problem. Until the exhaust was warm. When on E85 it has way less pops. Is that timing related as well? Or because the E85 burns with less intensity in general? After headers, i get pops on 92. None on E85. However, it appears to pop less with headers and no cats.
Drives: 2018 Camaro SS A8
Modifications: Roto-Fab Intake, E85, NW 103mm TB, 1 7/8" Headers/muffler delete, MSD Atomic Airforce Intake Manifold
150hp Wet shot on progressive control/standalone fuel system
It's all 100% timing related. With all 4 cats your pops will be much softer than with headers and no or high flow cats.
It's all timing related and also has to do with how fast DFCO kicks in. A hot exhaust does seem to help with the pops, but it is not the reason. When I do aggressive "burble" tunes the cars pop the most when cold because the Lambda is richer and DFCO/CFCO is disabled until they warm up.