Sunday, October 28, 2012 - 12:27 pm, by: Nem Jovanovic(Mrnamjama)
Hi folks
I had a full system installed by Neil on my v8 soarer a few months ago. On day one I could hear this puff/ticking noise from near the firewall when driving (only under load), but I figured it was probably the shims.
I had the shims fixed up (usual suspects were massively out of spec) and the noise at idle disappeared, but the ticking/puffing under load was still present Deafening and annoying with window down and accelerating past cars or walls...
So I took the car to an exhaust shop who found masses of pinholes in the welds, and a blown out gasket at the flange. All fixed (and H pipe replaced with X pipe), but noise remains on acceleration.
The exhaust shop guy said it's probably just the 4-2-1 extractors (these are the Rush extractors) making the ruckus and there's nothing to be done about it. I cannot quite believe that this is a normal noise - I can't hear it in any of the videos posted up by people who've installed Neil's headers...
I am yet to record this, but I will eventually...
Does anyone know what I'm talking about? I should NOT be able to hear a soft ticking under acceleration, coming from behind the EMV/transmission somewhere... it can be heard when accelerating at any speed - the harder I accelerate the louder it gets.
Sunday, October 28, 2012 - 02:28 pm, by: Nem Jovanovic(Mrnamjama)
when you say knock sensors not working - wouldn't that be obvious via actual 'knocking'? A couple of mechanics have seen and inspected the car and no one has mentioned anything along those lines... it's working beautifully as far as i can see, except for the annoying ticking/puffing sound
Sunday, October 28, 2012 - 03:13 pm, by: Dave Rose(Sand_groper)
Well its just a guess Nem, as i cannot think of any thing else!!,if the knock sensors were not telling the timing to back off you would get a tingeling/rattle sound but not puffing and not as loud as you say yours is, maybe it is the exhaust set up?
Sunday, October 28, 2012 - 03:40 pm, by: Nem Jovanovic(Mrnamjama)
You know, I just cannot believe that it's not the exhaust... and I specifically asked the exhaust shop guys to go over it with a fine toothed comb to find the cause. The answer was '4-2-1 extractors just do that', but that seems like a copout to me. Especially since I haven't heard other people complaining about Neil's extractors!
Mike Beck Goo Roo New Zealand BMW E36 Coupe 1UZFE V8 340i
Monday, October 29, 2012 - 11:13 am, by: Allan Langford(Allan)
did you use the supplied header flange gaskets? i promptly placed them in the bin, applied high temp silicon to both sides of the factory ss shim gaskets and had zero leaks.
can you post a video of these sounds your getting?
Wednesday, November 14, 2012 - 10:18 am, by: Nem Jovanovic(Mrnamjama)
far better.
As a bonus, it seems that the crack in the extractor was large enough to cause a lean reading in the o2 sensor, as well as muck about with the back pressure difference for the LHS and RHS cylinder banks - end outcome is that the car has significantly better pickup at low RPM, which is a happy and unexpected outcome...
Not sure yet whether there are any high RPM changes, but there is definitely significantly better pickup at low RPM - I'm looking forward to seeing new fuel economy numbers next month.