Alfa Romeo Forum banner

Can I get my exhaust to pop, crackle etc when lifting off???

133K views 38 replies 13 participants last post by  keepRolling 
#1 ·
I want to get the beautiful sound of the exhaust popping and cackling as I lift of the loud pedal. How does this happen and can I do anything to make it happen???? :p

Setup I have:

V6 Engine (GTV)
CDA BMC induction kit
Powerflow Centre box
Supersprint Quad Exit Exhaust



Sounds great at idle and thorughtout rev range. But no snap, crackle and pop when backing off.... .... I would love to hear the pops, any ideas????? :D
 
#10 ·
My 156 2.0 TS with 2,25" stainless steel straight through silences and racing cat made a nice burp when lifting off, and bliping the throttle.
It also did the occasional bang when I took it to the redline and made a quick gear shift.
But it also had C&B cams and no ecu optimization, so it migth not do it if the ecu was properly optimized.
 
#20 ·
£370 I think perhaps a little more.

It runs straight from the cat...the two centre boxes are removed and the rear box is smaller about the size of a cornflakes packet. The rear DTM style (my favs) were picked by me from a selection of rear pipes. NB these make no discernable difference to the sound. The pipe is almost straight and runs high and flat and through the rear wishbone so no kinks. Took a little fiddling with but an excellent job.

There are no problems with MOT but a word of warning, I believe it is 119db so some tracks wont allow it on track days.

DT
 
#22 ·
I'm not afraid to tackle the exhaust system DIY style, but was just wondering how much it was from LL :) cheers for that.

I just spotted this on the bay, which would suit the alfa 156's rear perfectly both in shape and appearance, and was thinking about using these or some of this to just switch the backbox on my 156. The original backbox's shape is a right pigs ear of a thing, so it would require some creative thinking to fit universal box.

I want something deep and sporty but not too loud, and doesnt look chavtastic
 
#24 ·
Its not necessarily fuel that causes over-run popping, its actually the addition of oxygen into the exhaust system. If you've got a small hole in your system, the burnt exhaust gasses (which on over-run can still be fuel rich) are allowed to burn again with the oxygen that is introduced to it. An inlet leak can also introduce oxygen into the system. My Kawasaki GPZ turbo had an inlet leak and that used to sound raucous on the over-run!
Guy
 
#38 ·
I had the same thing happen on my little 125cc. Breather tubes running to the exhaust had fallen apart so the thing used to pop like a proper big bike! :p Replaced the hoses, everything back and quiet again.
 
G
#28 ·
thats right I remember now..god i'm getting old..
drill a one eigth.. (thats about 4mm in napoleon).. hole upstream of any silencers.. I guess it will have to be after the lambda sensor..for the mot put an exhaust clamp and some gun gum over it.. it was a lot cheaper than twin webbers.. flowed and skimmed head.. cams like oxo cubes.. straight through pipe.. it was never ending.. and then your gearbox would blow up..
 
#30 ·
drill a one eigth.. (thats about 4mm in napoleon).. hole upstream of any silencers.. I guess it will have to be after the lambda sensor..for the mot put an exhaust clamp and some gun gum over it..
Or tap it and screw a short bolt in come MOT time. Does this harm performance though?
 
G
#29 ·
Also to make a supersport straight through silencer.. get a piece of one inch steel bar.. thats about 25ish mm..
hammer it through the silencer from the inlet to the outlet.. big hammer required.. look through it and if you can see the sky you have got yourself a 'sports silencer'.. those were the days...
 
#32 ·
basically you need to raise the rev limit of the cut off for the fuel.you lift off the loud pedal then the fuel supply is cut off. therefore nothing to fuel the overrun. if the fuel system can leak, say as if the throttle is @ 2000rpm then you will get your popping. i think
 
#36 ·
Let us know how it works out, maybe a recording too if you can :thumbs:

I'm sure it could be done because lamdba sensors are screwed into the exhaust pipe, I know they have a captive nut welding in place but its just the same :D
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top