problem alloytec sports exhaust help

[Breno]

hey everyone,

just put a sports exhaust system on my vz alloytec ute.

had it on for bout 2.5 weeks now that is extractors, high flow cats into a single 2.5inch cat back (two mufflers and a resonator) along with a custom tune.

Although i like the sound of it down low when it gets to about 3 000rpm i get
this annoying, resonating, raspy sound coming from under the front (not the engine, the cabin section) of the car.

makes me cringe ever time a hear it. lol. After 3500rpm it goes away

had a good listen and what i think it may be is when it goes from dual from the cats into the first single muffler, that it fights at that rpm who has right of way first and resonates inside the muffler and causes vibration, which causes the crap sound.

sorry if it sounds confusing and long but tried to explain it best i can. lol

thought it might be because its new but its not getting any better and should of broken in by now.

All im after is if any one has a personal experience of the same thing or just a opinion on what it is... cause it cant be normal, before i go running round exhaust shops trying to fix it!


by the way the tune is worth it makes all the difference! goes harder


cheers.

[andyman]

hmm that noise seems to be there on the factory pipes too, i think it might be from the intake cam changing it position causing the note change, obviously your exhaust makes it worse

[Breno]

yeah its not good but i just hope somthing can be done.

never really noticed that sound though while i had the factory system on....it was just so quiet all the time. pretty much why i changed it. lol

[Torquative]

if ya looked 2 threads from the top before ya posted this one you would have seen "VZ V6 Rattle" (VZ V6 Rattle!) and you would find theres already a topic with 89 posts about this same issue that a few of us are experiencing.

[Breno]

Arr damn... sorry bout that.

i just read v6 rattle and asssumed it had nothing to do with my vibrating/resonating problem.

pays to read everything first. lol

had a good read of it now and seems theres a few things in common with mine as well....except i dont get it at idle (thankfully) just 3000rpm.

have to keep seaching and hopefully find something to fix it.

thank for the heads up anyway.