Hi Folks

Just had a 3" Decat Turbo Back Blitz Nur Spec R system fitted. Car is a 2003 Sti but the system is for a Classic.

Now apart from the fact its verging on the ridiculous and the wife went nuts..........its also making an additional, quite annoying noise

Its a bit like the noise you sometimes get (in any car) when you have the window slightly open on the motorway. Like air is reverbarating in the cabin?

Anyone else experienced this? The exhaust was second hand but as I understand there isnt really much in an exhaust system that could be flapping about or causing this?

Only driven it at 3000rpm as well! Getting it mapped tomorrow. I dread to think what the fek its gonna sound like at 6500rpm!

Might be worth mentioning I had an RCM induction and new HRC fuel pump fitted at the same time.

Welcome any thoughts

Cheers

Stuart

 

I have something similar with my japspeed only really does it under load though, slight incline or a like.

Cant tell you what causes it, but i stopped or greatly reduced it with an exhaust bung.

But i was advised "not to kick its head in with it fitted"

Its just 2 bolts on the tail pipe :-)

 

i get this... its kind of like a helicopter of air noise
best i could explain it sorry

 

Yeah thats its! Like a friggin helicopter! Good description!

Ok so its not just me then! I dont have a bung unfortunately. I might source one though. Its almost embarrassing driving through the village

 

Weld the bung fixing holes up.

Or stick a nut and bolt on each one with a nylon washer either side.

 

Really that sounds like a waste of time in all honesty.

 

If you've fitted a stainless downpipe, you can now probably hear the air passing through the wastegate when on part-throttle. You'll also hear the whistle of the turbo more clearly. Quite normal!

 

Yep downpipe fitted as well. Would the wastegate'flutter' or be a constant noise?

Interesting thought on the bung bolt holes. Wouldn't have thought they were big enough to cause an issue.

 

Yes a full decat will give you more turbo noise, on a New Age STI without a remap it will also give you boost spikes and det, I take it you have had the car remapped at the same time as having the other parts fitted?

 

Hi Tony

Car getting mapped tomorrow. So I've only pootled home from the garage to my house when I picked it up (5 min drive) making sure I didn't boost up or go over 3k

 

Get this too. Found it slightly annoying at first but got used to it, only had it a month and don't even notice it now!

 

Does it do it on idle?

 

i cant say ive noticed it on idol on mine, i get it when im trying to stay at a constant speed say 30-40mph

 

Same for me. Ok at idle but hear it when cruising mostly. Just got back from having it mapped. Sounds like a fekin jet plane now! Awesome!

 

If it's only under load I would say it's just induction noise which you're not used to, having gone from an air box to an induction kit. The inner wing resonator acts as a damper for this on the OE setup but you won't be using it now.

My exhaust makes a chopping sort of noise when at idle as the air reverberates out of the bung mounting holes, just thought it could be a similar case for you.

You will definitely hear turbo spool and induction noise now you're on the RCM kit, have the same on mine along with a bigger turbo and it sounds nice

 

sounds like a bit of everything amplified, as i dont run an induction kit, im using a panel filter.. so could be the bung holes and turbo that i hear mostly