Advice on quieter exhaust options

[WADEY]

Hi, I am running a AW11 MR2 with a rev 3 turbo and was wondering if anyone has any experience of finding a quieter exhaust for day to day running. It currently has a dreaded powerflow exhaust which was fitted to get an MOT when the project was first completed. It comes under the car in 3 inch stainless pipe, then goes onto a Y piece and sweeps into two 2 inch pipes and tiny silencers. I believe this is why it is so boomy and must be creating back pressure.

I have been offered a 3 inch stainless through out into a large free flowing transverse box for £288. Would this make it alot quieter? It is my only car at the moment and is running great, but too noisey for me on the Motorway and A roads.

Any advice is welcome.

[cdwood2010]

The only thing that ever sounds quiet is either a custom made system or the original silencer. It's quite tricky finding a balance.

I wouldn't spend £288+ without hearing what one sounds like.

Personally I would find someone selling a decent second hand system that you can hear first, preferably before they remove it or one that you know what it's going to sound like (roughly) from another application.

You're likely going to have to do some fettling to get it to marry up, so it might be worth going for something slightly fast-road and if that's too noisy, fit an intermediate box in the middle.

On the Mk2's I generally like the standard looking slightly bigger bore systems. The really big bore (3"+) sound tasty but the drone on the motorway will send you nutty.

C.

[mrT]

I agree with Chris, the oem original back box will probably be one of the quietest, but can be slightly restrictive too, there are however quite a few companies that will make you a completely custom exhaust system and make it sound exactly how you want, but that does come at a premium

[snowtigger]

2 and a half is about right unless your going for big power then the 3 it is, most twin exits are rather loud and a custom one with single 4inch exit and large rear box will be quiet and be free flowing.

My twin exit exhaust was immensely loud lovely burble but droned at 70mph, I have a big bore single exit with a large box that's great but needs more rumble .

[Spook]

Ive just put a second hand Mongoose stainless system on a mk2 3SGE and its sounds brilliant... but its too bloody loud for everyday. Seemed to loose some weight compared with OEM and its definately free'er flowing.
To my surprise it doesnt sound too 4 cyl in a big can, which was a bonus, a V6 would sound brill thru it, but very loud.

tail pipes are 2.75 inch, no matter how I measure em.

I'm hoping that re-fitting a new cat instead of the current de-cat will knock a few decibels off!

[kalsingh1]

Is there such a thing has quite on normal driving or steady motorway speeds, but a devil when your foot is down ? Or is that just wishful thinking?

[racerADS]

I need to get under my car and find the details of my exhaust. Bought it on here a few years back. Think it came from big Chris's car when Paul did his conversion originally. It is nice and quiet when idling, comfortable on the motorway and sounds beautiful when you spank it.
Started her up in a leisure centre car park last night and the 9 year old getting in the car behind was utterly impressed. His dad looked gutted to be getting in his Kia.

I will try and get a vid or audio tomorrow.

[MMaddict]

Is there such a thing has quite on normal driving or steady motorway speeds, but a devil when your foot is down ? Or is that just wishful thinking?

There are some valve systems that open up when you rev it. You would want the mechanical over the (cheap Chinese) electric versions.

Some of the Audi TT exhausts usually come with a valve like that.

[Spook]

Of course one of the problems is resonance in the body, my exhaust seems to be causing a lot.

I dont know if the standard mounts can be changed to something a bit more compliant or if the booming just causes panels to vibrate remotely., I think I'm getting both.

On one of the MR2 forums some time ago I read someone talking about the mk2 rear arch panels & boot acting like a boombox and because the forward end of those arch cavities point at the cockpit, thats where a lot of noise ended up!
He reckoned that blocking the cavity (I think it was a plastic bag full of polystyrene) just after the rear arch would reduce the effect but there was a danger of to much condensation.

I was going to go and try it, but now ive put this exhaust on i might have a few more fundamental vibrations!

[mrT]

modern exhausts, bmw , audi etc come with a valve fitted on the exit pipes of the exhaust, which shuts one pipe or half closes it on regular inner city driving, and once the car is revved past a certain point the valve opens up, result is more sound and more flow...
check out the picture in this listing, will give you a rough idea what i mean
http://www.ebay.com/itm/05-BMW-M5-E6...-/260753772185