[1QuikWS6]

Originally Posted by E90Martin

Thread = Exhaust sound/ Drone
Argument you proposed = Exhaust Wrap
Exhaust Wrap = contain exhaust heat
=????
Sorry I dont get you, nor does my mom drive a civic. However, when she does get one I'll follow your tip and put on a fart can and see if it sounds the same. Anyways, the construction of let's say an active autowerke exhaust's construction is the same as a muffler delete, only with fancier piping and a helmholtz resonator that apparently doesn't remove drone. Before you make that general assumption, you might actually wanna go around and hear people's setup with the mod done.

I know this doesn't have anything to do with the reduction of drone issue of your thread - just thought I'd pass along the info to answer

Exhaust Wrap = contain exhaust heat
=????

Exhaust wrap is not typically used to alter exhaust sound/reduce drone/muffle sound but just a little info on benefits of exhaust wrap:

Exhaust Wrap = contain exhaust heat = not a bad thing

I've been drag racing muscle cars of one type or the other for many years - currently using my TransAm with Lingenfelter 427 LS engine + Nitrous

Well known trick amongst drag racers running in many classifications, trying to eek out every leetle bit of HP, is wrapping exhaust & it's benefits.

1. Increases Speed of Exhaust
   Hi temp exhaust gases have lower density than low temp exhaust gases. By insulating the exhaust system, higher temps are maintained, which in turn lowers the density of the exhaust gas. Lower density exhaust gases travel through the exhaust system faster - hence wrapped=better exhaust scavenging & more HP.
   
2. Increased Engine Efficiency
   Wrapped exhaust manifolds reduce heat transfer to the intake manifold. The engine operates more efficiently when the intake air is cooler. When the engine's intake manifold is subjected to the heat produced by the exhaust system, the intake manifold transfers the heat to the intake air, reducing engine efficiency. Wrapped = more HP
   
3. Reduce Intake Air Temperature
   Air intake systems draw external air through the air filter, through an intake tube, and into the throttle body. The air filter box and intake tube are heated by the air temp in the engine compartment. Reducing the air temp underhood around the intake components results in cooler air being injected into the engine, which increases the engine's efficiency (and overall horsepower produced). Wrapped=more HP
   
4. Increased Engine Life
5. Small changes in operating temps can/will extend the life of the engine and engine components. Insulated exhaust systems reduce the amount of heat transferred back to the engine.
   
6. Protect Electrical Components
   Electrical components exposed to the high temps of hot metal can melt and short. Wrapping electrical components in exhaust wrap insulates the electrical lines from heat and reduces the possibility of failure.
   
7. External Temperature Control
   Hot engine compartments can heat the hood to temps that might damage or alter custom paint jobs. For vehicles with high performance engines (including turbo systems), reduction of engine compartment temps can help prevent hood and hood paint deterioration.

I chose to not wrap my T/A exhaust (which is cheaper way of doing it), but instead, my entire exhaust system from the Hooker Long Tube Headers, thru the midpipes, to the chambered GMMG muffler, are coated Inside & Outside with JetHot Ceramic Coating. This equates to same results as wrapping, but is more permanent, no maintenance, albeit more $$ in the beginning.


And yes, I have driven in friends cars with both muffler delete & the AA system with the 'special' resonator. Latest was a 120mi trip with AA system. Drone was so bad between around 2200-2500rpm (cruising rpm) that by the end of the trip I just wanted to scream

Personally, I don't feel wacking off the muffler=good sound (just 'Hey look at me' loudness), nor would I ever do such a thing on a car that I use as a daily driver - but it's your car, free to do what you like & everyone has his/her own tastes


After this brief intermission - Now back to our regularly scheduled program

[hassmaschine]

I was actually trying to be constructive. yes, a wrap would probably have a similar effect and is a better idea than spraying your exhaust with something that's obviously flammable (even if it's still not a great one).

Originally Posted by E90Martin

Before you make that general assumption, you might actually wanna go around and hear people's setup with the mod done.

what, loud, farty cars with drone? no thanks, heard plenty of them.

it's just, people do stupid crap like this - and then complain that it's too loud/drones/whatever. well, duh - you removed the muffler. what did you think was going to happen?

then you spray some random goo on the pipes that will probably burn off and smell. I feel sorry for whoever ends up with your car after you.

[shadow191]

That stuff is basically spray on rubber/butyl. I don't think it will catch fire after it dries once the VOC's are gone. But I also don't think it will last very long. If anyone has ever had Dynamat sag from a trunk lid due to high heat, this stuff is pretty similar. It's rated to 300 degrees, but that part of your exhaust is usually 400+. I'm pretty sure if you crawled under there while your car was running, you'd see that the coating is soft. And eventually, the heat cycles will dry the material out and it'll probably crack and fall off. No big deal, but I doubt this will be a long term solution.

All this stuff is doing is mass loading the exhaust. It would be the same impact as if you used thicker pipes.

[cadenfarley700]

Originally Posted by E90Martin

A month ago, I decided to pull the trigger on doing the muffler delete as I wanted more umph from my exhaust. From the outside and during hard acceleration, it sounded great but the cabin drone was just unbearable. As many have said, its to a point where it's a bit embarrassing when I have people sitting in my car. For me the drone was from 2k-2.4k range, it might be a little different from mine because I put on a Vibrant resonator in place of the old muffler. Anyways, I've searched all over the forums and read every post about drone fix. Tried fitting corks onto the hangers as suggested by a few, did nothing to help (was so desperate i actually fell for it) . Read about Helmholtz resonators (j-pipe) but the calculations were so damn complicated and probably for the cost added together with the muffler delete I could've gotten half of a BMW PE.

Anyways, I read about those sound deadning mats on other forums and did some shopping on Amazon and found a spray type alternative. I got it today, did 2 coats around the area where people would normally put a Helmholtz resonator. boom 90% drone gone, even my steering wheel vibration from the exhaust drone during idling is gone.
Now the only downside of this is that the substance is black, so if you have fancy pipes and do not want to ruin it because you have people looking under your car, i would not suggest doing this. Furthermore, I do not know if this is permanent, as of right now the coat is holding up to the heat but I'm not sure if it would melt on excessive heat (e.g. long trips).

TL;DR
Spray boom mat on exhaust, fix drone

Link to product: http://www.amazon.com/DEI-050220-Boo...words=boom+mat


Note: Please spray at your own risk, do not get mad at me if it does not work for you/ ruins your pipes.

Can you post a picture of where exactly you sprayed the stuff? I sprayed it where my muffler used to be and it didn't really help.

[Fritzer]

I have had my muffler delete done and I don't really understand what people are complaining about as "drone". Sure it's much louder at highway speeds but nothing near "unbearable". My car is seldom under 3k when on the highway, even in 6th gear.

[avocet]

I had an AA gen 1 exhaust and I don't really understand how people can say they never experience drone.

But seriously, some cars seem to get it, some don't. Some people don't mind it, some people can't stand it. Some people can solve the drone issues with inventive means, others simply ditch the exhaust set up.

My drone, especially after catless headers, was unbearable and I removed my AA exhaust over it.

[6ixSpd]

Yeah, I've been back to a stock muffler after doing headers this summer. I much prefer the civility especially seeing as it's daily driven. I don't need drone on my morning commutes, too old for that shit lol.

Besides, with the AFE intake it sounds perfect when I am on it.

[GORDON.M3]

Originally Posted by 6ixSpd

Yeah, I've been back to a stock muffler after doing headers this summer. I much prefer the civility especially seeing as it's daily driven. I don't need drone on my morning commutes, too old for that shit lol.

Besides, with the AFE intake it sounds perfect when I am on it.

+1...

lol had a muffler delete on the N52 for a day and got rid of it. put back the stock exhaust and called it a day.

[Jimsbim]

I've got to give a shout out for the Rogue Engineering IKON muffler. I've got one on my 328 manual with no other exhaust mods. I wanted NO DRONE, and to hear the exhaust but not as much as a muffler delete. the more you get on it the more you hear it. No drone at all, at any speed. It costs less than a used BMW PE, mildly throaty sounding, and its a stainless steel high quality product.

[njpolako]

Muffler delete sounded great on my 06 330i

[CTinline-six]

Originally Posted by Jimsbim

I've got to give a shout out for the Rogue Engineering IKON muffler. I've got one on my 328 manual with no other exhaust mods. I wanted NO DRONE, and to hear the exhaust but not as much as a muffler delete. the more you get on it the more you hear it. No drone at all, at any speed. It costs less than a used BMW PE, mildly throaty sounding, and its a stainless steel high quality product.

You should post a video!

[CTinline-six]

This isn't directly related to BMWs, but I have exhaust experience from building Jeeps, and I can say a manual vs. auto absolutely has an effect on drone.

Some automatics depending on torque converter lockup, gear changes, engine load, etc, can really make drone a nuisance, where it might not be as noticeable or frequent with a manual in the same car.

For me, I enjoy an exhaust with a manual but not an auto. A manual car is more engaging to begin with, and the exhaust seems to enhance that experience as long as it is not too obnoxious. With an auto, it seems to just drone on as the car slowly rolls through the gears.

[hassmaschine]

Originally Posted by CTinline-six

This isn't directly related to BMWs, but I have exhaust experience from building Jeeps, and I can say a manual vs. auto absolutely has an effect on drone.

Some automatics depending on torque converter lockup, gear changes, engine load, etc, can really make drone a nuisance, where it might not be as noticeable or frequent with a manual in the same car.

For me, I enjoy an exhaust with a manual but not an auto. A manual car is more engaging to begin with, and the exhaust seems to enhance that experience as long as it is not too obnoxious. With an auto, it seems to just drone on as the car slowly rolls through the gears.

right? you can always tell an automatic with an exhaust - "BlehhhhhhhhBlehhhhhhhhhhhBlehhhhhhhhhhhhhhhh. .."

[Taskmaster]

I have exhaust parts for sale - Brand New $150 for a 3" muffler, 3" resonator and 2" to 3" Y pipe.