How to keep True Duals resonably Quiet

**Intrepidman** · 12-01-2010, 09:58 AM

I'm sure there are a fair number of people out there running true duals, but has anyone had much luck keeping such a set up relatively quiet...behind a 450rwhp+ engine?
I'm not going for "stock" quiet, I just can't have it too loud for everyday driving, and it MUST stay under 130dbs most of the time while I'm at the track. (regulations)

I'm wondering what mufflers would be worth trying and where/how people are hanging them.

**Schmalgar** · 12-01-2010, 10:10 AM

There are noise regulations at the track?? But it's the track!! Is that a common rule at tracks? Seems silly...

**stew215** · 12-01-2010, 11:41 AM

I guess if the track is near a development they most likely have a deal with the township to keep it under a certain sound level so the locals don't complain.

And from what I understand Magnaflow seems to keep the car at a decent sound level.

**tpilews** · 12-01-2010, 05:21 PM

Yeah, magnaflow is your best bet.

**cammed goat** · 12-01-2010, 05:56 PM

Originally Posted by Schmalgar

There are noise regulations at the track?? But it's the track!! Is that a common rule at tracks? Seems silly...

I can't remember if it's mandated by NHRA or if it is per track regulations, but there are noise restrictions.

**02Sweet** · 12-01-2010, 06:59 PM

Originally Posted by cammed goat

I can't remember if it's mandated by NHRA or if it is per track regulations, but there are noise restrictions.

Noise regulations is a per track/per event basis. Some tracks require mufflers some don't some events full exhaust etc...

**Blackbird WS6** · 12-01-2010, 08:02 PM

what true dual setup you have? out the back OR dumped before the rearend??

**TA98** · 12-01-2010, 08:12 PM

Spintech? Moroso Sprialflows?

**c5z28** · 12-01-2010, 08:15 PM

Going over the axle quieted down mine a lot. Currently my car at 4k reads 119 decibels. I have highflow cats with magnaflow bullets. Sounds great at wot but drones like a whore at 2k rpm. When my exhaust ended at the axle it might as well have been open headers, it's amazing what a few extra feet of pipe will do to quiet it down.

**Blackbird WS6** · 12-01-2010, 08:16 PM

Originally Posted by c5z28

Going over the axle quieted down mine a lot. Currently my car at 4k reads 119 decibels. I have highflow cats with magnaflow bullets. Sounds great at wot but drones like a whore at 2k rpm. When my exhaust ended at the axle it might as well have been open headers, it's amazing what a few extra feet of pipe will do to quiet it down.

true dat...thats why i asked...it makes a BIG diff