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I've recently put a new muffer on my exhaust as the old one was stuffed which is what I thought was making the car so loud..

It has taken some of the bark away but the car is still very loud and "droney".. The exhaust is 3" all the way through with a cat converter and a 5" cannon.

I've called up Right Price and they told me they could fit a resonator which might quieten it down a little, or they could fit a bit dearer one which will rob the car of some power.

My question is, what sort of power loss should I be expecting>????

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Just get a straight piece of pipe and weld flanges on it on both sides and on the resonator then you swap them whenever you feel like being louder and having (slightly) more power.

No way of telling how much power it will rob without testing on a dyno, purely speculation.

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It all depends on how restrictive the resonator is.

It could be 10rwkw, could be 20rwkw outright

Could be 15rwkw in the midrange.

It could also be ZERO (i bet you wanna hear that). If its a good design and flows well, no reason it will rob you of much (if any).

Have you looked into a second muffler perhaps?

That would also achieve, and if its again, of good order... you wont loose any power.

I intend to have an exhaust that whilst quiet, does not rob one iota of power. Its certainly can be done as there are many cars around that have not lost power due to a exhaust because it is free flowing

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I didnt notice any power loss when mine went in, to look into it, there was no restiction at all, it looked like a perforated pipe wrapped in something but the inside Dia was the same as my 3" stuff, I did notice that the bark was gone but the growl was still there mmmmm.

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Have a look at the muffler/resonator.

Ensure its 3" inside and doesn't step down.

Also ensure the perforated holes are smooth and don't stick in to the exhaust airflow. If they do.... you loose power.

My exhaust is quiet on cruise but loud when you open it up. It has the largest straight through rear muffler that fit.

post-382-1172571075.jpg

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the problem is that loudness is subjective

i personally fitted the largest resonator icould when i have my exhaust made as i was advised that the resonator is the biggest thing that controlls the drone

i think my exhaust sounds awesome but others might find it quiet

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you'll probably find that the resonator will be a straight through muffler anyway, so it shouldn't bring your power down much if any at all

Just have to be carefull of badly/cheaply made resonators as that is what kills power even if it is straight through.

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Mate I recently had an exhaust done at Pipewerkz on kestles road Mc gregor just near Clive Peters and JB hifi.

My exhaust is 3 inch with straight through resonator (u can get a small bodied on or a large bodied on for like $20 extra) I got the large one and a 3" straigth through muffler on the rear. the exhaust is very quiet. at idle it almost sounds stock.."almost".....it has a great sporty note and the only dorone i have heard is when coasting down a hill in too low a gear off the throtle (which is expected and no one drives like that - unless they are engine breaking down the said hill)..

Chat to Rob if you have not already had this done at right price.

Edited by turbs33
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I actually gained 14rwkw going from a shagged res to a full bodied muffler and the car wasn't as loud or droney on cruise or idle. Both were 3.5 straight through.

I reckon i have a muffler sitting at home thats bigger than your one cubes :wave: I remember bending the heat sheilds to fit it in

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Just have to be carefull of badly/cheaply made resonators as that is what kills power even if it is straight through.

yep, thats something i found out recently. even if they dont step down the size (3 inch straight thru) they can still cause turbulence which is probably worse. so good quality is what u need. u shouldnt lose any power at all.

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Ok today while I was at work my dad stopped in to right price to have a look at the resontor they were talking about. Turns out it was only 2 1/4" and it was more of a muffler than an resonator..

It was not straight through at all, just like a normal muffler.

The other one they showed him was an oval shaped muffler which was fairly large which had a small pipe going through the middle of a 3" pipe with straight pipe spirraling around it if you undertstand what I'm saying??

Anybody have any experience with something like this??

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Don't go for ANYTHING other than a 3" straight through. No fancy spirals or smaller inside pipes.

The muffler/resonator must have a 3" pipe through its guts and the holes must be smooth to both look at and relatively smooth to touch. No noticable metal protruding from the hole.

Going for anything less will loose power.

A large body muffler or large resonator that is straight through does keep noise down. The trick is for the muffler body to be large.

My exhaust is fairly quiet when cruising, and there is absolutely ZERO drone. Only when you flatten it does it roar. :(

And its a 10% straight through exhaust.

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I had a resonator fitted as I also just had nothing but a cat and cannon. $60 installed and it was great. I don't believe it caused the car much restriction.

Agree with Cubes. Don't get the ones that step down or up - make sure you can look through it and the pipe has nothing in the way as Cubes said.

Also, if your cannon is old it might just be full of crap and not doing any muffling. If it's f**ked get a new one and see if that helps. If it doesn't help enough get a mid muffler down from the cat.

Edit: Cubes- how's that look no the car? :(

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Get a resonator then :(

But if your cannon is new then you have to accept the fact it's going to be loudish, even with a res, which should just take some drone out.

If you want the cannon to be a lower in volume fit a bigger mid muffler, or ditch the cannon entirely like I did

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f**k the cannon off

That'll cut the noise straight away

I went from a massive cannon to a proper muffler on the rear with twin tips (High flow)

No change in power, much quieter, no drone

Yeh if this resonator doesn't do the job then that's what I will be doing. I wanted to go twin 3" pipes from the beginning but it didn't end up happening. Will see how I go anyway.

Anyone know some sites that sell what I'm after??? Or sponsers??

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