I actually was inspired by your thinking to research it further. Didnt mean to prove anything wrong, just on a never ending quest for more info is all. What the info does reflect is that a balance pipe will work as it changes the dynamic of the exhaust. there still may be a reasonate frequency that occurs somwhere in the rev range because of whatever reason but will be insignificant as it will only be passed on acceleration / decel etc. My mate is bit of a critic and at first was out to prove the theory wrong as were many during the post. instead he in fact came up with a theory that supports yours as well as adding in an extra dynamic to the picture overall. I am very impressed by the fact that you figured out a fix that would work for most and I only wish I had thought of it before I ripped my engine down only to find that there was nothing wrong and I had wasted a lot of cash. I would agree and recommend that the balance pipe be tried above everything else due to its financial sense. All I was trying to figure out was why it worked and the reasons behind it. No offense intended. sorry Mungyz
oh :stupid: I guess stupid may be me then LOL! I read the post the wrong way I guess. Maybe I am just a little touchy about it seeing as there seem to be a lot of know alls out there who knew all about this but in fact don't know jack. I apologise also.
Effect on Performance? Does fitting a balance pipe to an aftermarket exhaust affect the performance? I would think it might disrupt the flow... After fitting the dumps and test pipes I too have also got the white smoke at idle. Before the car only had a cat-back and it was fine. However, it also had the AIV system and now it's removed. I was certain that the removal of the AIV system is what was causing the smoke and all it needed was the ECU to be re-programmed to cater for the AIV delete. I've read on a few other Zed forums people having this smoke problem and when they installed an aftermarket chip it got rid of it. And most chips have the AIV delete. But after reading this, I think I'll give it a try. It does make a lot of sense. My other conclusion was not enough back pressure due to the absence of cats. This could also be a factor...but I see in this thread that even the people with Cats had the smoke...so Balance Pipe might be the solution...and if it was in the original exhaust, they put it there for a reason... Cheers Rob.
got mine done today, the viabration i had when i pulled up at lights has gone, or on cold start when the rev's gradually went down, it used to viabrate.. gone. sound's cleaner, and slightly different.. more.. 'even' tomorrow i'll see if the smokes gone. looks pretty crap but oh well
and the smoke is gone.. i cannot say how happy i am.. thank god i saw this post!! for the others, dont wait do it now!
X Pipe or Balance Pipe? Well now I'm confused... I thought an X pipe would have a similar effect to a Balance pipe (H pipe). My current setup is dumps and test pipes joining up to an X pipe muffler...see pic below... Then just straight pipes out to rear mufflers. So no H pipe/balance pipe, just this X muffler instead. The car still smokes after idling for a couple of minutes. My question is...is there a difference with a balance pipe people are fitting vs. an X pipe system? Or should they both have the same results...? Should I still add a H pipe somewhere? Cheers Rob.
both the same thing afaik,an x-pipe will give better flow,but ive never heard of anyone having both in the same system
X pipe too soft? Yeah me either...that's why I thought I'd ask first... lol Maybe the X pipe isn't as strong as a H pipe when it comes to cancelling out what it's supposed to...and that's the problem. I don't know... Maybe it's because I don't have Cat's either...but then again, there are people on here who replied who don't have cats and have the balance pipe and they don't smoke... If I can avoid installing the cats back in I will...that's what I'm getting at... Cheers Rob.
There is no need for back pressure. I think the theory was explained very well earlier on. In regards to back pressure This is not the case, but it has to do with the pulses that form in some exhasuts not all. I mean look at my system on the track car if the car needed back pressure to not blow smoke I think mine would do it. Food for thought, Mungyz has stumbled (sorry, about that) on a very cost effective cure for smoke that may not address all smoke issues. His result certainly made me go back and look at the theory as I have always been told that turbos destroy the pulses in the exhaust system...... but we know now that it not always true.
exhaust keep in mind that the reason for the smoke is likely related to the dynamic of your exhaust. there are more than two ways to configure an exhaust to achieve the same natural frequency. The reason why the H pipes worked could have been because they adjusted the exhausts dynamic such that the natural frequency occurred at a different point in the rev range and therefor didn't cause resonance of the seals. this could have been achieved by heavier turbo seals, Cats, different mufflers, exhaust tip etc. If you read through the post as well you can see that there are a few people that have had the problem without cats and then with cats back in, the problem goes away. Feel free to correct me if you don't agree but I believe that the pipe acting as a balance of the two exhausts is not why it works. It works simply because of the change in resulting natural frequency. In that light, you may have changed your exhaust from stock but the changes may result in the same problem frequency being reached at idle. you could try a few things to change that. Im still learning so I hope that is a help.
Problem Solved! Different Solution... Ok... I thought about it some more...did a bit more reading and thought I'd try something different in an attempt to fix it. The car idled slightly higher than it's supposed to, around 1,000rpm. Firstly I fiddled with the TPS adjustment. I found that even by moving the TPS in different spots the amount of smoke which came out either reduced or increased...weird? It didn't go away though. I cleaned the TPS connections and then I adjusted the idle screw on the IAA unit. I only wound it back a quarter turn and it adjusted the idle to maybe 50rpm less...it was hardly noticable...I disconnected the battery as well when I adjusted the TPS and then reset it. I started the car up and to my surprise, no smoke! I left it sit there for 10 mins and still no smoke. I took it for a drive around the block and back home again...let it sit at idle for another 10 mins...NO SMOKE! Could adjusting the idle also change the dynamic of the exhaust? It was only a minor adjustment but it seems to have worked... Cheers Rob.
that was a great idea! can you tell me if the note of the exhaust has changed at all? like more drone, less drone volume level?
Slightly less drone... Less drone at idle and more bearable now. Almost sounds normal, but still beefy. The sound has changed slightly I would say... Cheers Rob.
therefore more likely a forced vibration issue. the natural frequency of your exhaust was very likely to have been forcing the seal in the turbos to vibrate. Similar to some of the advice in this thread. the change in revs has probably stopped exciting the natural frequency of the exhaust and thus not forcing a vibration of the seal any more. other option would have been if the exhaust still droned a bit......revs might have been exciting the natural frequency of the seal itself. this is of course much less likely tho. good to hear you got it sorted
can i ask why you dont want to run cats,surely not because of restriction as there is sfa in a quality high flow ???
Sure... You sure can ask... The simpler the system, the better the flow. You'll notice it a lot more if you are running boost. At least I have anyway...it made a big difference when I removed them... Cheers Rob.
i still say you should get the balance pipe in, its no secret that we have been able to get rid of the smoke by having it idle higher till operating temp.. at the end of the day the frequency problem is still there your just giving it less chance to rear it's ugly head, fit the x pipe it will do the same thing as a balance, and sound better. also as for cats, the smoke didnt go away when i installed mine, it just didnt smoke as much due to the cats burning most of the smoke.
