Hi everyone i recently did an exhaust upgrade on my 2006 v70 2.5T. i had a remap done as well. I wanted a magnaflow setup ...so i did:
3" DP
3" high flow cat .....MagnaFlow 99956HM - MagnaFlow Heavy Metal Catalytic Converters - Overview - SummitRacing.com
hi flow resonator ....MagnaFlow 10426 - MagnaFlow Performance Mufflers - Overview - SummitRacing.com
and wanted a magnaflow muffler but got a mystery "no name" muffler (baffled)
so now i find i have quite a bit of drone..mostly around 1300-2000 rpm..usually when engine is under load (but not a WOT) and on cold start-up when the rpm's come down to around 1000rpm...
any advice? the resonator? muffler? bad fitment (internal pipes)?? bad motor mounts?
thanks
fabs

 

Chambered mufflers (also called baffled) can produce drone, IF the metal for the muffer is thin, thicker, heavier steel mufflers almost eliminate this.

Furthermore, exhaust pipe gauge affects drone also for what you here inside the car, thicker = quieter.

If you only here it when you got the window down, the drone is just the sound the muffler creates, no real way to get rid of it beside getting a different muffler. A straight through will be (could) raspy at higher RPM.

 

LIFE... thank for the info. For the muffler, i guess it does vary. For the dnomax that i had on originally, at the shop, there was a demo one that was cut open to show the inside and beside some (wool/ figerglass?) insulation, the actualy metal seemed thing..and this chambered one? not sure...
I did originally ask for magnaflow as i like the sound of it...are they good mufflers? do they generally have more insulation within the metal structer to help with drone?
I went to another shop and they where showing me their resonators that they make that they say really helps with drone...know anything about the magnaflow res. that sould be on there? are they good products?
The drone is actually with the windows up, my brother has a 1998 v70 r, with aftermarket catback and custom 3: downpipe and it has a nice sound and when driving there is no drone like what i have..
will find out this week..i'll see what this shop says when they'll look at my car.
fabs

 

get a straight through magnaflow, 24 + inches body length. Magnaflow are good mufflers for the money, but AREO mufflers are 5 times better, and 5 times the cost. You get what you pay for with straight through mufflers. Chambered, look for a "delta flow" type baffle system, chambers have no "filling" and use sound waves to eliminate unwanted freqs like drone, 300 Hz and lower.

add: Drone actually causes hearing damage because the freqs at which it occurs are more intense than you actually hear.

 

LIFE..thanks again. Aren't most (universal) mufflers around that length to begin with? so what you are saying, is that just a regular chambered muffler can actually be more noisy then the "free-flow" magnaflow muffler you where mentioning?
for my year car (2006 v70 2.5T, chipped) what magna type/model muffler would you suggest that fits in well? what's the story with tips? is it just a cosmetic thing or functionality? i always read about people and the tips they put on?
thanks
fabs

 

tips are mostly for looks, the resonated tips (I like MONZA) help more so than other brands.

yes, chambered should get rid of most of the drone, you might have drone certain rpm range (ie. 1200-1500 rpm) where you may have it still.

straight through are way louder, however they sound wicked with turbos. MHO

MagnaFlow Exhaust Products - For Trucks, Suv's, American Muscle, Diesel, & Sport Compact Vehicles

MagnaFlow Exhaust Products - For Trucks, Suv's, American Muscle, Diesel, & Sport Compact Vehicles

first one for straight through is 30 inches, thats perfered, however you might have trouble fitting it. second link is the 24 inch one.

Fro chambered, its all about brand preference. I have a Xcelerator muffler made by some off brand. It is a flowmaster knock off and sounds better, plus it was $20.

Cherokee's exhaust, PT II - YouTube

 

Hi gang, just a little update, i did change out the resonator and muffler (for hi flow), it is better then before but still a tad drooney at times. I wanted to know though, is the size/shape of this particular cat. good for my car? can it also account for some of the drone? i tried getting some reviews on it, but looks like they are mostly used on trucks and bigger cars? thanks
fabs

 

no the cat actually acts as a super resonator getting rid of a lot of rasp from the exhaust. With out it the exhaust will be higher pitched on take-off and louder cruising.

Keep in mind though where you put the muffler (s) under teh car makes a huge difference for how much drone you hear.

 

hey, thanks for the reply. I know that the placement does make a difference. I was just curious about the cat though, as it is a bit bigger (like a big football) in size, i figured with the big size, it will add to extra vibration and noise, where as if it where a bit more sleek (bullet shape) there is less room for terbulance inside.
fab