Aero Muffler Evaluation

Lin · February 25, 2020, 10:11:11 AM

We went on a 400 mile round trip this past weekend, which was the first trip since installing the Aero muffler. It is really loud! At first I was a bit concerned that CHP would be doing u-turns when I passed them, but no such thing happened. Of course, it seems less loud when up to speed-- just sort of like being on a jet liner. And when the Jakes are on, the clatter is truly impressive. It is clear why some jurisdictions try to ban compression braking.

On the positive side, I do believe there was a bit more power. I topped an 8% grade coming home at 28 mph in 2nd gear. As I remember it, that is faster than before. Also, the muffler has gone a long way to dealing with wind noise issues. Since it is not summer, I do not know if it affected engine temps. Nor do I have enough of a sampling to say anything about fuel mileage.

I now ask myself if, knowing what I know now, I would do it again, and I can't answer that question yet. When we first started the trip, I probably would have been against it, but by the end of the ride it did not seem to be as intrusive. I have noise canceling headphones that I use for air travel. If I decide to use them while busing, that would be some sort of indicator though.

luvrbus · February 25, 2020, 10:30:56 AM

Lin add a turbo and it makes it just right

the N/A engines are just loud

Lin · February 25, 2020, 11:14:32 AM

Adding a turbo would certainly improve several things, but I do not think I am ready for that. What would the cost of such a project be? Is there room in the 5a engine room?

TomC · February 25, 2020, 01:05:58 PM

There's room-but you have to be clever where you mount it-usually to the side of the engine. Believe me when I say it REALLY wakes up the 8V-71. I went from N65's with 300hp and 800lb/ft torque to 7G75 injectors with 375hp and 1125lb/ft torque. Good Luck, TomC

chessie4905 · February 26, 2020, 05:01:22 AM

Tom, I always wondered why you stayed with such a numerically high rear.

TomC · February 27, 2020, 01:21:24 PM

I stayed with the 4.56 since the V730 has an .88 overdrive built into it. And since it is only a 3 speed (think of a HT740 without 1st), and the fact that reverse is a gear between 1st and 2nd (I once did over 40mph in reverse in a big empty parking lot-could of gone faster, but chickened out), the only other gearing is the 4.1. But I like the startability and I can get lockup in 1st gear as low as 20mph for either climbing or Jake braking. I cruise at 60mph which is right at 1,900rpm. I once took it up to 2,400 which was 75mph-way too fast. I'm quite satisfied with the combination of startability, hill climbing, Jake braking, cruising at 60mph with the 4.56. Good Luck, TomC

chessie4905 · February 27, 2020, 01:51:11 PM

There is a 4:27 also.

luvrbus · February 27, 2020, 02:10:28 PM

A old bikers trick to quite down the Harleys was to drill and install a bolt through the pipes made a huge difference in the noise level on the bikes ,I am going to do it to mine,lol the Harley sound is not what it used to be to me anymore but I bet it work the same on bus may need a larger bolt than 5/16th though

Lin · February 27, 2020, 05:29:27 PM

Sounds like installing a bolt would be cheaper than installing a turbo. I's be curious to see what that looks like.

Van · February 27, 2020, 05:49:06 PM

Quote from: luvrbus on February 27, 2020, 02:10:28 PM
A old bikers trick to quite down the Harleys was to drill and install a bolt through the pipes made a huge difference in the noise level on the bikes ,I am going to do it to mine,lol the Harley sound is not what it used to be to me anymore but I bet it work the same on bus may need a larger bolt than 5/16th though

A 5" pipe? Hmmm I'll guess a 7/16" two thirds across the dia of the pipe might do it lol!

Mufflers? we don't need no stinkin" mufflers.

Dave5Cs · February 27, 2020, 07:15:35 PM

Speaking of OL Biker's........LOL

luvrbus · February 27, 2020, 08:25:47 PM

Quote from: Dave5Cs on February 27, 2020, 07:15:35 PM
Speaking of OL Biker's........LOL

Van is a pup I ride with a guy that is 88 years old plus he still flips drivers the birds,nothing has changed expect the desert plants get watered more often now

Lin · February 27, 2020, 09:14:44 PM

Am I correct in guessing that the location of the bolt is in the pipe after the muffler? If so, it could be tested by temporarily securing a bolt inside the pipe to see if it really did anything before starting the butcher the system.

DoubleEagle · February 28, 2020, 05:01:07 AM

Would more than one bolt make a difference? Straight pipes studded with bolts?

luvrbus · February 28, 2020, 05:49:56 AM

I have no mufflers and my pipes are 30 inch header pipes.you may could try a C clamp and see if it makes any difference Lin,I don't if it will work or not in your case,I know mesh will make a turbo or blower quite installed on the cold air side