Resonators do they reduce noise or change tone?

[~SlideWays~]

I just fitted a mild steel exhaust which I made for my jzx100 Chaser (1jzgte vvti single turbo). It is using the standard downpipe then goes to 3" mandrel bends to a single oval muffler at the back. The muffler is from chase (same as pitstop) with three chambers, the two ends are packed with fiberglass.

Now it sounds nice revving in the garage but I took it for a test drive and it's way too droney and surprisingly it is also raspy!

The only thing I can think to do is fit a big resonator, which will have to be about in the middle of the car closer to the rear. Will this actually make it quieter or just change the tone?

The other option is to try fit a second muffler but I'm not sure that will fit.

Any suggestions on resonators?

Cheers

[rolla_fxgt]

We just had the same dilema with our legnum.

Had a few rust holes in the resonator, so took it out and put a straight pipe in, and it hasn't changed the loudness at all, in fact if anything its made it slightly quieter, but it has changed the tone to a higher pitched, slightly raspy one at one particular point in the rev range.
Makes it sound less manly in its sound, like its had its balls chopped off, vs before when it had a bit of deepness to it.

[~SlideWays~]

We just had the same dilema with our legnum.

Had a few rust holes in the resonator, so took it out and put a straight pipe in, and it hasn't changed the loudness at all, in fact if anything its made it slightly quieter, but it has changed the tone to a higher pitched, slightly raspy one at one particular point in the rev range.
Makes it sound less manly in its sound, like its had its balls chopped off, vs before when it had a bit of deepness to it.

Hmmm cheers for the feedback. I really need it to quieten it down at part throttle/cruising speed.

Its strange, I googled it and some people say they make it quieter and other say it does nothing.

[Stott69]

Resonators change the resonant frequence (pitch). An oval off set muffler will quieten down a system best

[sergei]

in my experience resonators take out 'rattle'/rasp type of noise, at least on NA, they don't quiet it down much, but they affect perception on the noise as it attenuates the noise where the ears are the most sensitive to the exhaust noise.

[rolla_fxgt]

I think the technical explanation as to why they change the sound is that they slow down the passage of air, by giving it more room to move, which gives it a lower tone. It doesn't have any 'stuffing' in it to also muffle the sound, so it just changes the pitch.

Just like a pipe organ, the small pipes are hight pitch, and the big pipes are low pitched.

[~SlideWays~]

Thanks guys, what about resonators that include fibreglass packing, will they muffle noise at all?

If I fit a second muffler will it still have the raspy noise meaning I need a resonator as well?

EDIT: are the Chase/Pitstop resonators any good?

[~SlideWays~]

Rang Chase and the guy reckoned resonators don't really reduce noise just remove the high pitch rasp.
Their resonators are reasonably cheap at $110 for a 18" one but not really worth doing if its not going to reduce noise.

So I'm thinking of forking out of an AdrenalinR oval type one like this:
http://www.adrenalinr.com/productdetail ... ductID=534


Problem is it Stainless Steel so can't weld it myself.

[e30-323ti]

You've done exaclty what I did (albeit with a TT 1JZ).

I ended up with the Flowmaster Delta 40 in the middle.
Quitened it up nicely, still had a bit of a drone ~2500 rpm which I put down to the nasty oval chase muffler.

I then bin'd the chase muffler and now only have the Delta 40 at the rear, which a a bit rowdy, but nowhere near as droney as the chase oval.

not much help sorry.....

[Bling]

Problem is it Stainless Steel so can't weld it myself.

Why not? I can understand if your whole system is stainless. But I though you could weld stainless with mild steel wire? Hmm, Google suggests that it may be brittle with CO2 gas used but that argon/CO2 mix might be alright. Doesn't sound ideal though. I'll shut up now..

[~SlideWays~]

Problem is it Stainless Steel so can't weld it myself.

Why not? I can understand if your whole system is stainless. But I though you could weld stainless with mild steel wire? Hmm, Google suggests that it may be brittle with CO2 gas used but that argon/CO2 mix might be alright.

Yeah I've done it before (I use argon mix) but was under the impression it doesn't bond as well. Maybe I'll just give it a go if I get some SS.

[~SlideWays~]

You've done exaclty what I did (albeit with a TT 1JZ).

I ended up with the Flowmaster Delta 40 in the middle.
Quitened it up nicely, still had a bit of a drone ~2500 rpm which I put down to the nasty oval chase muffler.

I then bin'd the chase muffler and now only have the Delta 40 at the rear, which a a bit rowdy, but nowhere near as droney as the chase oval.

not much help sorry.....

That's a bugger to hear... guess I'll see if its still droney after fitting something in the mid section.

[Akane]

Just had 2 x adrenalineR's put in, more effective than a single angled Chinese exhaust.

[jacobrjett]

sorry to thread jack,

so if resonators make it sound deep without a rasp but dont remove volume,

if i were to decat and replace the mid muffler on my standard ae111 exhaust (with resonators), would i be able to achieve a slightly deeper and more aggressive exhaust tone on my car and keep the stock muffler for stealth look?

[sergei]

sorry to thread jack,

so if resonators make it sound deep without a rasp but dont remove volume,

if i were to decat and replace the mid muffler on my standard ae111 exhaust (with resonators), would i be able to achieve a slightly deeper and more aggressive exhaust tone on my car and keep the stock muffler for stealth look?

stock rear muffler does most of the job. if you remove middle muffler (the factory resonator) it will add rasp (but be quiet otherwise). Same with replacing cat with straight through pipe.

If you are on the budget what you can do is go to pick-part and find a muffler that is of larger diameter piping (one size) and replace factory one with that. That will make it sound deeper without it sounding teeny.

[rolla_fxgt]

sorry to thread jack,

so if resonators make it sound deep without a rasp but dont remove volume,

if i were to decat and replace the mid muffler on my standard ae111 exhaust (with resonators), would i be able to achieve a slightly deeper and more aggressive exhaust tone on my car and keep the stock muffler for stealth look?

You could replace it with a bigger resonator, as Sergei has said, I'm pretty sure the mid muffler isn't a muffler, but a resonator.

Bigger reasonator ='s more volume, thus lower/deeper tone

or as sergei said remove the cat, and put a resonator in there.

[e30-323ti]

You've done exaclty what I did (albeit with a TT 1JZ).

I ended up with the Flowmaster Delta 40 in the middle.
Quitened it up nicely, still had a bit of a drone ~2500 rpm which I put down to the nasty oval chase muffler.

I then bin'd the chase muffler and now only have the Delta 40 at the rear, which a a bit rowdy, but nowhere near as droney as the chase oval.

not much help sorry.....

That's a bugger to hear... guess I'll see if its still droney after fitting something in the mid section.

I've still got the 3" chase oval in the garage somewhere if you wanted to try 2 of them...

[Kiwi-Corolla]

Had a similar problem when I replaced my exhaust and removed the cat. Ended up being raspy as hell and droned quite badly on the motorway in fifth gear. Experimented with a few different resonator sizes until I found a set-up I was happy with. Luckily I took a video after all three attempts and uploaded them to YouTube

See my post in this thread for the YouTube links: viewtopic.php?t=88470&highlight=

[sergei]

on my AE101 it took me 2 longish resonators to stop it from droning.

[~SlideWays~]

Bah!

So I fitted an expensive AdrenalinR resonator (40cm/15" body), its a very nicely made thing with proper louvres and stainless steel wool packing. I put it as far forward as I could, which is basically under the drivers seat.

It got rid of the raspy harshness and quietened it down a decent amount but its still horribly droney with any acceleration and cruising at 50 or 100.

So now I'm thinking, do I fit a 2nd muffler before the diff? Or is this Chase oval muffler just a shit design and will be droney no matter what is in the exhaust before it??