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????
all straight through silencers and keep the pipes as straight as poss.. cherry bombs are cheap.. just get stuck in with some pipe and a welder..might have to bin the cat
My bike used to do this before I had the fuelling corrected on the dyno. Well sorted fuel maps shouldn't pop unless you have valve overlap or something like that.
You could try a decat so the unburned hydrocarbons aren' converted to CO2, it may work
Yes, that is the cause as far as I am aware. Some high performance turbo cars put unbuned fuel through the engine on purpose to help the turbo spin (anti-lag) and that creates a nice bang too.
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.
Straight through from the cat back... stainless... (except your pants) Tip on the the over run slightly touch the pedal, but not enough to propel the car, if you know what I mean. v gentle.
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.
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
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
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! Replaced the hoses, everything back and quiet again.
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..
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..
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...
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
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
It could of gone a lot better! The downpipe was that corroded it pretty much folded up at the whisper of a drill! Gutted, and im not attacking my new one just yet!
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