I'd ignore those neighbors. It sounds like they're the type of neighbors that would be ringing the local authorities on a full moon night complaining they can't sleep because it's too bright.
research papers rarely have practical application --but here is info from one which may be of benefit --For the optimal design of a muffler, the following frequencies should be avoided 15Hz, 30Hz, 45Hz, 60Hz, 75Hz, 90Hz, 105Hz, etc. in order to avoid the resonance. From all the frequencies, the most important frequency is 90 Hz EFR. The wavelength at 90 Hz is 20 feet, so the length of the tail pipe must be exactly 5 feet to avoid resonance
The problem isn't your exhaust system, the problem is that your neighbors are too close. I wouldn't live in such close quarters with other people. If you do you have to put up with their crap. Enjoyed this long drive as it shows how well the shift points have been set up.
Now that would be an achievement if you could devise/invent a silencer for these venerable General Motors Diesel engine two-strokes. The Company I worked with back in the '70's were selling/service dealers for General Motors Terex heavy equipment. Along with this and from our Parts Departments, we were selling a muffler system called 'Cowl Mufflers', which seemed to reduce the sound of these engines quite a lot. I wonder if these are still available?
I'm not sure, I'm running two resonators, a 12" and 24". In cab is very quiet, and just the right sound coming from the exhaust. I've considered trying one of those new Cummins engine covers and see if it makes any difference. I'll have to look into the Cowl mufflers and see.:)
@@detroitgarage9430 Good thinking on the Cummins cover,.. I wonder too, if Cowl is still in business as my experience with those is a tad dated now! I'd like t see what you come up with.
I love how your driveway looks like that with the oil spots. These older diesels like to *mark their territory*! I can relate, I have a '00 7.3 with a lil drip where I park. I had another e'99 7.3 with a lot more than a drip coming from it - it had a leaky, rusty oil pan, and the passenger rear oil rail plug on the back of head was leaking also(the o-ring gets cooked cause the downpipe goes down right next to that plug). So I'd just add oil rather than doing the right thing and fixing the actual problem! I just kept a half sheet of old OSB under it to catch my mess.🤔🤦🏻♂️😅🛢️🛠️🔧🔩🛢️👍🏻👌🏻
That's from spilled veg oil.:) Unfortunately I spilled quiet a bit of veg oil from collecting and filling the tank.:) I'll pressure wash that off in the Spring cleanup.:)
If the exhaust system is already quiet as it can be, the intact tract could be another opportunity for noise reduction. It sounds great to me as is, but it is nice to be able to take that sound and just lower it down a few notches.
In the future I'm considering adding a 5" exhaust, turbo back. I think this and a better resonator will cut down on the snapping sound,:) The intake is about as quiet as I can make it using the Ford OEM paper filter.:) In can the turbo whistle and engine noise is just about perfect. I'm considering trying to fit a Cummins 6.7 engine cover on it and see if that makes any difference.:)
@@detroitgarage9430 What style of mufflers do you currently have? I have a huge Donaldson muffler on my 6BT that works really well, it has a mesh screen basket that the gases get pushed through and then an open chamber for cancellation. The sound is very tame and it seems to have killed the bass and mid range frequencies, but there is still some turbo whistle which is nice. Adding a perforated core with packing style resonator would likely take it a step quieter but in my case there’s no need.
@@detroitgarage9430 You could definitely kill more noise with a more effective muffler. The Donaldson I have is 44” long and 9” diameter, huge but very effective. Fits with plenty of clearance under my 2006 F-250 CC/LB. Take a look at the Donaldson muffler catalog, lots of good information in it to match one of their mufflers to your engine.
HP--you may have come across this presentation--- authored by PE a few miles north of me--Engine Exhaust Noise Control--JGL Acoustics, Inc--eye opening
I do see a lot of signs banning Jakes, but none about exhaust noise.:) I think most places use 92 dbls as a bench mark.:) I'm right around that level.:)
Angry? They are blessed to be able to hear this baby in person. I say delete the other 2 and let her sing! =) All joking aside, I think she sounds great. Not sure why they are angry, its not like your drifting through the neighborhood at all hours bouncing off the rev limiter or anything. =)
It sounds just fine, it dontneed a bigger better muffler... Straight pipe that unit, and watch them all scream... You need nicer neighbors, or they need better ear plugs...
Evil thought : drive a Commer Knocker home some evening 😈. Seriously though, how much of that is exhaust and how much is cam gear train + blower noise? you can't do much about the gear train I expect, or the blower. The exhaust you could always put on a much quieter muffler with a bypass valve for when you are out of the neighborhood, and "quiet mode" for calming the neighbors as needed.
We had a soft drink truck in the 70s with a Commer Knocker. You could hear delivering in streets for an hour before it got to us. We then changed soft drink companies and they had a delivery truck with the Detroit Diesel. I have no idea what Detroit was in it but it was much quieter than the Knocker. There was a main road not far. There was a paper company that had a fleet of single drive tandem axle and bogie drive Dodge trucks that I found out recently all had 6V53s (I'm now a truck driver and one of my truck driver mates was telling me his father used to drive for that company so that's how I eventually found out what engines were in those paper trucks). Man those 6V53s made nearly as much noise as the Commer Knockers when loaded with these huge paper rolls. The Knockers were the loudest apart from unmuffled 16V567 locos ascending the local hill. At 03:00 every morning was the crackling drone of a 727. That was about the only part of my childhood I miss. No rose coloured glasses for the past here LOL. The present is far better in most ways.
@@ThePaulv12 I grew up in Darwin, NT, Aus. There was a truck company who had a Dodge Prime Mover with a 6V53. It would pull 3 trailers (115 ton!) from Darwin to Jabiru a couple of times a week. That poor thing made so much noise it would scare the birds from a kilometre away!
