The Forward Look Network | ||
| ||
413 New Yorker Exhaust Drone Jump to page : 1 Now viewing page 1 [50 messages per page] | View previous thread :: View next thread |
Forward Look Technical Discussions -> Engine, Exhaust, Fuel and Ignition | Message format |
1coolbanana |
| ||
Veteran Posts: 267 Location: Sydney | Hey guys
Edited by 1coolbanana 2018-09-05 8:00 PM | ||
Shep |
| ||
Expert Posts: 3393 Location: Chestertown, NY ( near Lake George) | Anything you do is kinda experimental. Some exhaust extensions can also cause this. | ||
Powerflite |
| ||
Expert 5K+ Posts: 9604 Location: So. Cal | Glasspacks in oval containers do drone more - at least all the ones that I have tried. If you replace them with turbo style mufflers, that would help. Also, it is best to get them as long as possible. 16 inches isn't very long, but it looks like you may have to do some re-routing to fit longer ones in there now. For that reason, I don't like to angle the mufflers like that. Also, I don't really understand the benefit of putting the exhaust right next to the driveshaft. | ||
1coolbanana |
| ||
Veteran Posts: 267 Location: Sydney | Would you consider adding a hot dog or resonator further upstream of any benefit? The local shop reckons an H pipe but I have my doubts. | ||
Powerflite |
| ||
Expert 5K+ Posts: 9604 Location: So. Cal | Anything extra will help, but you will be increasing the back pressure too. I have tried H-pipes and it didn't change things very much. Not worth the trouble in the end. | ||
57chizler |
| ||
Expert Posts: 3768 Location: NorCal | I'd try to fit a resonator in the tailpipe if there's room, size will depend on your pipe diameter. https://aeroexhaust.com/i-30497562-aero-exhaust-resonator-tr20-tr-se... | ||
wizard |
| ||
Board Moderator & Exner Expert 10K+ Posts: 13042 Location: Southern Sweden - Sturkö island | Take a photo on your end pipes - you have what looks like the very same system that I have on my '60 Saratoga and I have no drone in any conditions. Is the butterfly valve frozen partly shut? | ||
1960fury |
| ||
Expert 5K+ Posts: 7385 Location: northern germany | What Chizler said, tailpipes. | ||
1coolbanana |
| ||
Veteran Posts: 267 Location: Sydney | 57chizler - 2018-09-07 5:53 AM I'd try to fit a resonator in the tailpipe if there's room, size will depend on your pipe diameter. https://aeroexhaust.com/i-30497562-aero-exhaust-resonator-tr20-tr-se... Thanks for that Does the resonator have to be in the tailpipe? Dont think I have room there but I would have in the engine pipe before the mufflers. . Edited by 1coolbanana 2018-09-06 8:46 PM | ||
1coolbanana |
| ||
Veteran Posts: 267 Location: Sydney | wizard - 2018-09-07 5:57 AM Take a photo on your end pipes - you have what looks like the very same system that I have on my '60 Saratoga and I have no drone in any conditions. Is the butterfly valve frozen partly shut? Butterfly vavle? If thats the assembly that used to be part of the cast iron manifold, it appears to have been removed decades ago.
| ||
fravizo |
| ||
Regular Posts: 68 Location: Stockholm Sweden | I´ve got the H pipe 1.8", exhaust pipe 2.5", oval mufflers 20" long and at the interval between 40-50 mph the car (New Yorker 61) drones. Quite a loud and impacting sound. I´m also looking for some solution to this. Johan Edited by fravizo 2018-09-07 6:27 AM (EXHAUST H PIPE.jpg) Attachments ---------------- EXHAUST H PIPE.jpg (247KB - 153 downloads) | ||
wizard |
| ||
Board Moderator & Exner Expert 10K+ Posts: 13042 Location: Southern Sweden - Sturkö island | Ok, it seems like that the both of you have the very same exhaust systems as I have. The butterfly valve is indeed the valve in the right exhaust mainfold - if it's removed it means that it cannot cause this type of probems. The Saratogas and New Yorkers should have a front muffler as well (and Imperials) - I don't have these front mufflers and no drone at all. So, since the tail pipes are the same as mine, your solution might be to install front mufflers (resonators?) or resonators in the tail pipes (Exhaust.png) Attachments ---------------- Exhaust.png (118KB - 143 downloads) | ||
BigBlockMopar |
| ||
Expert Posts: 3575 Location: Netherlands | Installing a dead-ended piece of extra pipe, T-connected to one tube of the exhaust can help greatly reducing drone-noise. Length of the added tubing is important and needs to be tuned/calculated to the exhaust. Exmaple; | ||
wizard |
| ||
Board Moderator & Exner Expert 10K+ Posts: 13042 Location: Southern Sweden - Sturkö island | Smart - a pulsation damper!!!!! Great - thanks for sharing | ||
BigBlockMopar |
| ||
Expert Posts: 3575 Location: Netherlands | I had doubts what it was called again in my previous but remembered this setup is usually called an exhaust helmholtz resonator. Look it up with Google Images to get the idea. | ||
wizard |
| ||
Board Moderator & Exner Expert 10K+ Posts: 13042 Location: Southern Sweden - Sturkö island | Ok, Helmholtz resonator - thanks' for the correct name Herman. Practically it works like a pulsation damper (usually installed in water pipe systems). | ||
wizard |
| ||
Board Moderator & Exner Expert 10K+ Posts: 13042 Location: Southern Sweden - Sturkö island | Marc, I saw in your other photos that your car has straight end pipes coming out under the rear bumper - on the phot above you have the "correct" end pipes. Which version has the droning sound? | ||
1coolbanana |
| ||
Veteran Posts: 267 Location: Sydney | wizard - 2018-09-08 11:38 PM Marc, I saw in your other photos that your car has straight end pipes coming out under the rear bumper - on the phot above you have the "correct" end pipes. Which version has the droning sound? Pretty much the same. Although Im driving it a lot more more! Could that little bit on the end be responsible for the drone?
Edited by 1coolbanana 2018-09-09 5:29 AM | ||
wizard |
| ||
Board Moderator & Exner Expert 10K+ Posts: 13042 Location: Southern Sweden - Sturkö island | I really don't know Marc, but judging by your photos we have the very same exhaust system and the engine difference is only 30 cui. Just demount the extensions and check which result you'll get. If you like to keep the tail pipes under the bumper, then I recommend that you clean all the chrome and wax it very often……... | ||
1coolbanana |
| ||
Veteran Posts: 267 Location: Sydney | Extensions are welded | ||
fravizo |
| ||
Regular Posts: 68 Location: Stockholm Sweden | BigBlockMopar - 2018-09-08 12:56 AM I had doubts what it was called again in my previous but remembered this setup is usually called an exhaust helmholtz resonator. Look it up with Google Images to get the idea. Thanks, very interesting should be a "game changer" to that annoying drone as I read so far and it's worth a try to figure out how to measure and where to place the dead ended T-pipes, after an accurately tuned in engine. Just a thought, cut the H-pipe in the middle and close the openings. Maybe not a good idea as some say that the H-pipe lessens the drone sound Another thougt, the tailpipes are cut horizontically to the ground, could that create resonance to the trunk and the gas tank? Yet another thought, have I got too large a volume in the 2.5" exhaust pipes? (DSC_0589.JPG) Attachments ---------------- DSC_0589.JPG (248KB - 131 downloads) | ||
BigBlockMopar |
| ||
Expert Posts: 3575 Location: Netherlands | I don't think for one minute the end of a full exhaust-system has any effect on causing drone or not. Droning is a combination of either both mufflers producing the same noises which are amplified, and/or cause floorboard-sheetmetal to resonate along with the muffler noise. I also think the type of exhaust hanger could be a good candidate for causing interior noise/drone. Is the exhaust hung on the frame rails (near the mufflers), or, for instance the bolts of the rear seatbelt brackets? How much rubber is used between the hanger and the mount on the car? Also lack of proper (heavy/tarmac) sound-deadening could 'help' the drone-noise carry itself further into the cabin. | ||
1960fury |
| ||
Expert 5K+ Posts: 7385 Location: northern germany | BigBlockMopar - 2018-09-11 2:30 PM I don't think for one minute the end of a full exhaust-system has any effect on causing drone or not. But i do. At least in my car, it has. | ||
fravizo |
| ||
Regular Posts: 68 Location: Stockholm Sweden | Good info, will check the hinges close to the mufflers if they could emit vibrations, whether the rubber isolators is large enough and as a obvious step should be to dampening the interior of the trunk floor, wheel houses and against the back seat might do a difference. Gonna check this company: http://www.swedac-acoustic.com/products/luftljudsabsorbenter/ And to figure out if there's any drone effect of the downward pipes if i attach straight pipes/flexible tubes to those Thanks, for a lot of useful approaches | ||
BigBlockMopar |
| ||
Expert Posts: 3575 Location: Netherlands | Besides droning issues, sound-deadening itself is usually a multi-stage process. Low/heavy noises require heavy material (butyl) to suppress. Higher pitched noises like road/tire/wind-noise require a lighter material like foam to dampen properly or best. You can see how (60-70's) luxury cars like Chryslers and Imperials where build in the day. They had heavy butyl-plates put directly on the floorboards, and 1" thick foam-insulated carpetting on top of that for added 'silence' and driving comfort. | ||
1coolbanana |
| ||
Veteran Posts: 267 Location: Sydney | I wish I had some of that padding in mine! The droning has improved with more use. Perhaps the glass pack is soaking up the oil | ||
Jump to page : 1 Now viewing page 1 [50 messages per page] |
Search this forum Printer friendly version E-mail a link to this thread |
(Delete all cookies set by this site) | |