AeroTurbine in and sounding GREAT!

[Car_nut57]

DLeno,



I'll tell you what, if you want to try an Aeroturbine in your 4" exhaust and are not satisfied with it for any reason. I will buy it back from you no questions asked provided you use band clamps for the install so the part is not damaged. I can't tell you for sure what results to expect and I don't see how I could ever come up with test data that would be conclusive. That is why the exhaust makers never publish specific EGT reductions or performance information. They may say up to such and such, but that is about it.

 

[Steve M]

I have to chime in with an apple to oranges comparison. I have a set of Dyno-Power (tm) staggered dual muffler pipes on my Harley. I've tried everything from drag pipes to a 2-1 Supertrapp header. I keep going back to the Dyno-power staggered muffs. They use the same concept as the Aeroturbine as far as a straight through design that allows a kind of expansion chamber type baffle. They're quiet when putting around but have a nice mellow tone with little rumble. But they'll speak up with some deep authority when the loud handle gets a twist! If the Aeroturbine will do for my truck what the DP muffs do for my Harley, I'd likely be happy with it. But I'm happy with the sound of my stock exhaust and EGTs aren't too high with stock power. It would only be a novelty for me. The throaty exhaust note of a Cummins is every bit as appealing as the throaty exhaust note of a Harley. To make it heard is a good thing!

 

[DLeno]

Thats a fair approach. perhaps I'm more sensitive to the validity of a given experimental approach than some, and maybe the reason why there's no detailed data is becuase not many care as much as I do. I want to emphasize that the reason I'm skeptical is because Aeroturbine claims better performance over any other after-market free-flow muffler. I hold them no more responsible to acheive advertized results than any other muffler mfg, but it turns out that they are making claims that others are not: lower EGTs than any other design because the magic aerofoil is supposed to suck out more hot air from the manifold. If thats true, then we have an extraordinary market contribution. If thats not true, then shame on them.



What I will accept at face value without challenge is that the magic sucking aerofoil will have a characteristic sound. I'm certain of that, and there are good engineering reasons why. I'm sure they sound great and I don't mean to discredit any claims in that regard. two might even sound better!



What they haven't proven is that the actual amount of air leaving the exhaust manifold is greater because of the magic sucking aerofoil. They've claimed it but haven't proven it. I'm only surprised because this would be extraordinarly easy to do (simple muff substitution and a dyno), yet no one has done it, and I am left wondering why.



so again, I appreciate the no-risk offer (and also for the PM which I'll read in just a moment). thats the kind of approach that will help guys like me validate results. I only wish I had more miles on my 04 (actually I wish I HAD my 04) and was ready to change exhaust right now! I tell you what, though, at some point I would be highly interested in some dyno time while subsituting muffs. If only we could see comparitive and controlled data from the use of an Aeroturbine, against two or three others and a straight pipe!

 

[Steve M]

You can add me to the list of skeptics as far as performance gains goes too. Anti-reversion cones and expansion chamber type mufflers do help evacuate the combustion chambers on a gas engine at certain rpm if it's a tuned system for the motor it's being applied to. Each exhaust pulse helps pull the next pulse out like they're holding hands. If it's not tuned for the particular engine it can actually rob power from it. The exhaust pulse will bounce off of the atmosphere, back up the pipe and crash into the next pulse sending it back into the combustion chamber. Thise is why drag pipes aren't the best for normal riding performance but they sure sound good!

Turbocharged diesels are a different story. The turbocharger is the most restrictive part of the exhaust. It needs a length of pipe for velocity but the exhaust pulses aren't going to evacuate the combustion chambers after being pulverized by the turbo. A tuned muffler six feet down the pipe isn't going to do anything for it but make it sound good. If it breaths freely it'll help EGTs.

Just my $. 02

 

[DPKetchum]

I found the stock exhaust to sound like a stopped up vacuum cleaner. Only sounded OK very low speed and maybe at idle. I used the Banks kit and got a easy 1 to 2 mpg gain from the get go. Still sounds good at idle and cruise with a authoritative sound when on the pedal and shifting. Very happy with sound and performance. Came with a new turbo outlet also. Banks claims a 18h. p. improvement over stock. I believe it.

 

[Car_nut57]

DPKetchum,



You are absolutely right, we have seen and heard great results with the Banks exhaust system as well and their new muffler design does incorporates an expansion area near the inlet which seems to help prevent drone.

 

[JStieger]

Originally posted by DPKetchum

Still sounds good at idle and cruise with a authoritative sound when on the pedal and shifting.

While waiting for traffic to clear before entering the highway, a black O3 with a small Banks stickers on the side of it pulling a big 5th wheel passes by in front of me. I could still hear the truck about a block away while starting to pull a slight grade and shifting throught the gears, but it wasn't obnoxious at all. I don't know if he had the Bank's exhaust or not, but if he did I was pretty impressed with the sound. It sounded a lot like a straight piped 1st generation - only about 25% or so quieter.



DPKetchum, is it possible for you to post a sound clip of yours?

 

[DPKetchum]

DO WHAT. I'm still in the DARK ages try trying to post pictures(LOL) Wife says it sounds like a big rig without being annoying.

 

[DLeno]

There is good engineering and physics behind the sonic qualities of various expansion chambers. As a matter of fact, any time there is a discontinuity in the pipe, there will be soundwave reflections, which can have an enormous impact on the sound. A discontinuity is a sudden geometry change (diamter increase, decrease, whatever). Depending on the placement of a muffler, resonator, or magic aerofoil, you will get cancellation of high frequency components in the pipe itself and a deeper sound quality to the exhaust.



Steve M makes an excelent point about tuned exhaust systems, the effect of the turbocharger impeller, and the applicability to gas engines as opposed to the CTD. Since sound waves within the pipe travel a lot faster than the actual air flow itself, you can achieve vast sonic differences while at the same time affecting EGTs only marginally if at all. Since the velocity of air in the exhaust pipe is comparitively slow, EGT control is accomplished by average molecule movement -- literally the number of molecules that exit the pipe per second.



So I think that we should be careful to measure the success of a particular device's claims against the claims themselves -- if the magic aerofoil presents a broad enough bandwidth (not subject to tuning) behavior, sucking air out of the turbo impeller under various conditions, impeller spoolup, and engine loads, then we should measure that success by looking at EGTs under controlled conditions. If it simply presents an average air restriction that is lower simply due to internal geometries, then so be it -- EGT is the right indicator, and the Aeroturbine needs to be compared to a few other straight-through mufflers to validate the claims.

 

[JWillms]

Originally posted by RDietze

alright ntenna, as you requested (as my arm is being twisted)... ... you are crazy! at $195 a pop (per aeroturbine muffler) i have a very diffacult time conceiving buying ONE of them.

Sorry to bring this back up but Holy Highway robery Batman where are you buying these things, the balck market? Is that just for 1 muffler? I bought one about 2 week ago the first day are truck supply dealer got them in stock (was the first person in town to buy one ) and I got it at $90 out the door and had some friends help me weld it up. I love the sound of mine, its the loadest at about 1500 when I go from crusing to get on it to pass in city traffic. Other then that it quit on the open road at crusing speed and I dont wake up the bloock when I start her up early in the morning. Im not sure if my EGT or MPG are lower becuse I havent hooked up the gauges yet (its in, just needs the probe hooked up) and Im still in break in mode so my MPG suck (plus I have had a heavy foot with my new muffler ) Over all I cant say anything bad about it.

Justin<><

 

[DPKetchum]

Put my Banks system on at 4k or so. Mpg was up 1 to 2 instantly. Was noticeable from the get go.

 

[RDietze]

Originally posted by JWillms

Sorry to bring this back up but Holy Highway robery Batman where are you buying these things, the balck market? Is that just for 1 muffler? I bought one about 2 week ago the first day are truck supply dealer got them in stock (was the first person in town to buy one ) and I got it at $90 out the door and had some friends help me weld it up. Justin<><

jillms; yeah, sorry you brought this up again



dieselpowerproducts sells the aero for close-to 2 bills, that's $200. heck, i would have seriously considered the aero for 90 bux . i asked dieselpower... if they would sell me one for $90 and i would buy it yesterday = no deal.

just put the banks monster on this weekend, it is OBNOXIOUSLY QUIET - how in the world banks got a straight-through muffler to quiet the exhaust down that much is quite a feet -- i don't like it. but i'm stuck w/banks now. best 4" exhaust, but too quiet for my liking... . and WHERE IS THAT TURBO WHISTLE?????

i have a bhaf on the intake side.

03 ctd ho

 

[DPKetchum]

If mine was any louder I'd be unhappy! Theirs flows over 900 cfm compared to stock which is near 300cfm. I thought the Banks system was fairly loud.