15 replies to this topic

[lx308]

I threw a 12" stainless hotdog on each pipe before the mufflers to quiet my old hatch down. Worked well
There's a pic here http://www.gmh-toran...22-wa-lx-hatch/

Edited by lx308, 28 April 2014 - 10:54 PM.

[N/A-PWR]

sounds like a Free Flowing Exhaust you have there Clint,

thicker pipes would stop the ringing. Dave I

[dattoman]

Solid flange plates with perforated holes that reduce the flow enough to quieten it down for rego

Don't put the boot in though

Just place them between a flanged join

[N/A-PWR]

not sure if Hot Dogs are legal yet. Dave I

[rexy]

A pair of resonators bought the LJ from about 105db down to 97 db. A partial occlusion aluminium plate covering half the pipe diameter at on flanged join on each side of the system was enough to get it under 96 db as required for SR plates in Victoria. I didn't notice a change in power when the resonators went on. Twin 2.5 inch system, straight through single rear muffler each side, no crossover pipe.

[darway43]

I just had a resonator fitted to my LJ also. Brought the noise (music/harmony) down about 10 db. Was still around 97-98 but they were happy to pass it.

[myss427]

Have 2 Sonic Turbo mufflers on the A9X only, quiet as a mouse until you push the pedal to the floor then sounds brilliant. Motor has over 400 horses and they don't seem to restrict it in any way. Cheap also from Jegs, about $80 each plus freight.

[A9X]

don't see them listed ?

[LXCHEV]

Hi Clint,

 

I've played with my exhaust a fair bit over the years, so here's some comments that may help.... (mine's a 450HP Chev with Tri-Y's)..

 

Started with a full twin 2.5" system, one muffler per side (straight through with expansion chamber style).... a little loud, and a bit "thong-slappy".

 

Next up, fitted two 10" resonators (hotdogs) - one per side, before the mufflers. This definitely toned the note down a touch. I've heard as a general rule of thumb resonators will bring the volume  down around 3dB. I also believe they are more effective when installed further down the system (ie. as far back as possible).

 

Finally, I fitted an x-pipe up front. This toned the note a little more again, removed a lot of the thong slap, and made it sound much nicer. Other mates of mine have had similar comments with the x-pipes toning the note a touch - so I'm guessing they could be worth another dB or two (or possibly more). It's hard to say without doing formal testing.

 

My system has flanges everywhere, so when I want the car to be more angry, I can quickly remove the tailpipes and run dumpers before the diff. The difference is fantastic. This also allows flexibility to play with different tail-pipes for low cost. I remember a decade or so back, I had a 2nd set of tailpipes made up.... tiny little 2" ones with hot dogs in them, which fitted either side of the drop-tank (I needed to clear an EPA or something from memory) and worked like a treat. Small tailpipes, and hotdogs as far back as possible are very effective at pulling down the dB.

 

Another mate of mine replaced his straight through mufflers for triple flows, and we actually did test that back to back with no other changes - they removed several dB, but I can't recall the exact figure.

 

Also - try to install the biggest (physical) mufflers that you can fit. The Hooker aero-chambers that you mentioned are very popular, but they're definitely not a quiet street muffler.

 

It's all just about trying different things to achieve what you need. Just do yourself a favour and use flanges!!

 

Cheers.

Edited by LXCHEV, 29 April 2014 - 09:43 PM.

[myss427]

don't see them listed ?

 

Sorry bought them a few years ago, they have been taken over by Walker. Part number is:

 

Dynomax#289-17733

Super Turbo Muffler

 

• In/Out: 2.50"
• Overall Length: 18.50"
• Shell Length: 14''
• Body Diameter: 4.25" x 9.75
• Offset In / Center Out

$44.99

 

http://www.jegs.com/...arentProductId=

Edited by myss427, 29 April 2014 - 10:17 PM.

[A9X]

ta mate

[ls2lxhatch]

I don't mind if its a little quieter permanently (I know my neighbors would be happy) I just don't want to restrict the motor... Well im in two minds, some situations (most the time) I like it loud but occasionally something abit more discreet, maybe after rego I'll look into Varex mufflers or maybe just a bypass valve.

 

Last time I checked the Varex style mufflers will only pass rego if they were a factory option. The cutout valves will not pass rego if they can be controlled remotely.

 

My system is 2.5" with a magnaflow x-pipe and mufflers. You can borrow it for a sound test if you want however I suspect it will also be too loud. Norm Bulter makes mufflers if you can't find anything suitable off the shelf.

 

Edited by ls2lxhatch, 29 April 2014 - 11:40 PM.