Exhaust sound

General Discussion about the Datsun PL510
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vtech010
Posts: 7
Joined: 20 Mar 2015 14:30

Exhaust sound

Post by vtech010 »

Hello all. I have. 1972 510, I hate the sound of the exhaust. My car has a sr20de. Does anyone on here have this setup? I would like to hear what your car sounds like. Someone told me to go with vibrant brand muffler.
datzenmike
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Joined: 24 May 2006 12:40
Location: Van. Isle.

Re: Exhaust sound

Post by datzenmike »

Sound is both personal and subjective and no one can know what you want or like. First thing is to know what you have and don't like so we can move in a direction away from this to something you do like. For example it might have a 2 1/2" into a fart cannon so I would say get a turbo style muffler (not anything you can look through) and if still too raspy put a resonator in front of it, perhaps a glass pack.
"Nissan 'shit the bed' when they made these, plain and simple." McShagger510 on flattop SUs
yenpit
Posts: 1700
Joined: 07 Jul 2006 20:14
Location: Denver Colorado

Re: Exhaust sound

Post by yenpit »

So a later model twin cam engine will ultimately sound like a Honda etc, especially if you have what many refer to as a "fart can" muffler! Like datzenmike said...........both personal & subjective! I sold hundreds of stainless mufflers & exhaust systems for Sport Compacts (Honda's etc) back in the day. The cheaper the muffler, the louder. One of my favorite brands was MagnaFlow...........very nice quality with good quality "packing material" inside & lots of shapes & sizes!

Is your car too loud, too quiet, pops too much.........??
How big is your exhaust piping?
Do you have a resonator somewhere in the middle under the car?
What kind of muffler do you have at the rear?
1973 510 2dr
1972 521 flat bed
1972 510 Wagon parts car
2009 Toyota Matrix S AWD

LOTS of 510 parts!
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Tedman
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Joined: 01 May 2008 22:06

Re: Exhaust sound

Post by Tedman »

Using mandrel bends will go a long way towards making it sound good. I really like the Borla stainless steel universal turbo muffler, Summit p/n BOR-40658. It has a center 2 1/4" inlet and an offset 2 1/4" outlet, 14" x 7 7/8" x 4 1/4" (LxWxH) and fits properly in the stock location. I've used it on both my SR20DE car and my L-series car (both street cars), along with a bullet or glass-pack style muffler alongside the driveshaft as a silencer. There's also a 2 1/2" version, but might be a bit large for an SR20DE and certainly louder. Here you can see how it fits:

Image

Image

FWIW, here's a track day GoPro in car vid in my SR20DE car so you can hear it, though I think the audio may be dominated by the intake.
https://drive.google.com/file/d/1HGboKY ... sp=sharing

And here's clip, also from my SR20DE car, with good audio where I set the cam up under the rear bumper to view the left rear suspension.
https://drive.google.com/file/d/18Xt-oG ... sp=sharing

Hope this helps!
BrianE
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Joined: 13 Feb 2015 09:39

Re: Exhaust sound

Post by BrianE »

I have the same exact year, model, engine setup and question as the OP. Currently I'm using 2" SS mandrel bent pipe from the collector back to a Magnaflow Universal muffler. It certainly "farts" like no tomorrow on deceleration(s). Under hard, quick accelerations thru the gear box it's acceptable noise wise. However, for prolonged driving on the highway at speeds between 60 -80mph in 6th gear (0.7664) I'm measuring 85-95 decibels on my iPhone db meter App. I've read that resonators do not reduce the decibels but rather reshape the sound wave to give the impression of being quieter. I know little if anything of how glass packs work. So I guess my question is, is there a known muffler out there that will cut the decibel levels at highway cruising down into the 70-75 decibel range? If this is asking for a bit of a "Unicorn" should I be taking an approach of using a Diff with a final drive ratio which would yield lower RPM's up and down thru the gears. My use case is simple daily driver with some fun out n' bout drives amongst the twisties every now and then...
datzenmike
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Joined: 24 May 2006 12:40
Location: Van. Isle.

Re: Exhaust sound

Post by datzenmike »

Generally the more resistance to flow (back pressure) the quieter it is. Magnaflow are first and foremost about good flow and loudness is secondary. A 'muffler' that can demonstrate a power increase will sell, to do this resistance to flow is lessened and sound level goes up. It's hard to get around this. To a point, more noise sells 'mufflers' too. You want quiet get a $25 cheap universal 2" muffler and leave the tail pipe off. This is what I have and you can definitely hear the car idling in the driveway outside. It's good at highway speeds also.

Resonators are designed by the car maker to attenuate a certain RPM drone. It's not an illusion, it is quieter, (barely) but only at that certain speed.
"Nissan 'shit the bed' when they made these, plain and simple." McShagger510 on flattop SUs
BrianE
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Joined: 13 Feb 2015 09:39

Re: Exhaust sound

Post by BrianE »

Circling back in the hopes that this will help others re this topic. Decided to invest in a 24" long 4" outside diameter resonator and have it installed at local exhaust shop here in the Vancouver WA region. True to all things I've been told and read here and elsewhere, the resonator paired with the 2" SS piping from the collector, resonator, magna flow turbo style muffler did not reduce the decibel levels at any rpm. Pretty much identical readings as prior to the install on my iPhone decibel App. However, the "reshaping" it did of the sound waves made a huge improvement as to what I subjectively here in my ear(s) as I wind my way up thru the gears till cruising at 65 or above and then it pretty much sounds the same as before. I'm going to drive it for a while in this config and do the mpg checks over the next couple of fill ups to see what impact it has if any on fuel consumption. More to follow...🌻
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icehouse
Posts: 3885
Joined: 17 Jul 2005 17:06
Location: Everett Wa

Re: Exhaust sound

Post by icehouse »

I had two cars with the NA SR in them. 1 sounded terrible the other sounds great. Here is a video clip of the good one. the good one is mostly 2.25" stainless with resonator and muffler. Can't speak the the driving decibels since it's a stripped solid mounted everything racecar.


https://www.youtube.com/watch?v=YpOASzj1iVs&t=18s
"People don't like it when shit doesn't match their rule of thumb." Sam
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