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What are the downsides of dumping exhaust before rear axle?

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Old 09-28-2009, 11:07 AM
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What are the downsides of dumping exhaust before rear axle?

If any, what would they be?
Old 09-28-2009, 11:10 AM
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Re: What are the downsides of dumping exhaust before rear axle?

At low speeds & idle, exhaust gas coming up inside the car.

Increased interior noise, especially if the tips are aimed down & the sound echoing up, into the car.

If you do it, I suggest taking it to the side, for a side turn-out, just before the back tire.
Old 09-28-2009, 11:33 AM
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Re: What are the downsides of dumping exhaust before rear axle?

Yeah I figured the interior noise would come into play, but I plan on getting a relatively quiet muffler. I'm sure there's more I can I do dampen the interior sound, too. I was planning on running it to the sides and dumping at 45* with or without a tip, haven't decided yet. I was referring to performance when I asked the question, although I didn't specify that, would I lose high end, low end, or anything?
Old 09-29-2009, 01:44 PM
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Re: What are the downsides of dumping exhaust before rear axle?

The only other thing I could think of, would be some street car classes your exhaust has to come out behid the rear axel.
Old 09-30-2009, 09:14 AM
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Re: What are the downsides of dumping exhaust before rear axle?

long term, exhaust gases are caustic to anything that is petroleum based, so it'll rot out your bushings in the suspension...
Old 09-30-2009, 03:04 PM
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Re: What are the downsides of dumping exhaust before rear axle?

If you have your underside and axle painted up all pretty like. its gonna coat it all with exhaust. I had my truck all painted blue underneath and it was all black in a couple months. the exhaust exited before the rear axle on it. I Found that puting turndowns angle down and out it kept most of the exhuast going out from underneath.
Old 10-02-2009, 01:26 AM
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Re: What are the downsides of dumping exhaust before rear axle?

If you drive or park in a gravel, or dusty area (pits at the track, etc) it's gunna blow a lotta dust up. Mine have always been turned down and out before the axle, and i don't mind it...just be aware that if your beside others when you start it up, or move, they may get pissed if your blowing dust all over their junk. + side is during burnouts, it blows the tire smoke out and makes it groovy lookin! ...LOLOL
Old 10-02-2009, 03:50 PM
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Re: What are the downsides of dumping exhaust before rear axle?

"At low speeds & idle, exhaust gas coming up inside the car."

I will second that. The possibility of carbon monoxide poisoning.
Old 10-02-2009, 05:44 PM
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Re: What are the downsides of dumping exhaust before rear axle?

Alright well forget dumping at the rear axle then, thanks for the replies
Old 10-02-2009, 05:48 PM
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Re: What are the downsides of dumping exhaust before rear axle?

Just turn it out to the side, not a complete dump UNDER the car.


Old 10-02-2009, 05:53 PM
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Re: What are the downsides of dumping exhaust before rear axle?

I would but I live in an area where they don't fix potholes and manholes stick up 3"
Old 10-04-2009, 04:57 AM
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Re: What are the downsides of dumping exhaust before rear axle?

It may tune the exhaust for an RPM higher than your powerband.
Old 10-05-2009, 10:57 PM
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Re: What are the downsides of dumping exhaust before rear axle?

Originally Posted by Stephen
Just turn it out to the side, not a complete dump UNDER the car.


Those are Porsche tips on the bird no?
Old 10-05-2009, 11:01 PM
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Re: What are the downsides of dumping exhaust before rear axle?

Originally Posted by usamuscle892
Those are Porsche tips on the bird no?
No clue....Just pics I've found.
Old 10-06-2009, 11:39 AM
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Re: What are the downsides of dumping exhaust before rear axle?

That blue car has to loud as hell for the passenger! haha
Old 10-06-2009, 01:35 PM
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Re: What are the downsides of dumping exhaust before rear axle?

My car is setup like the blue camaro pictured but my exhaust dumps on each side right brfore the rear tires. If you do go that route you muffler choices are limited and usally have to go with racing mufflers.
Old 10-06-2009, 02:53 PM
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Re: What are the downsides of dumping exhaust before rear axle?

Originally Posted by chcgobearsfan3
Yeah I figured the interior noise would come into play, but I plan on getting a relatively quiet muffler. I'm sure there's more I can I do dampen the interior sound, too. I was planning on running it to the sides and dumping at 45* with or without a tip, haven't decided yet. I was referring to performance when I asked the question, although I didn't specify that, would I lose high end, low end, or anything?
Dude to be honest I love the idea of dumping the exhaust like that. As far as fumes I havent had a problem yet and I been in bumper to bumper traffic so pretty cool. And as interior noise well its up too you I love the sound of my car and the vibration that the exhaust releases, and im runing the flowmaster 1 chamber muffler with a magna flow high flow cat and no headers.

I also have exhaust clips on my youtube. www.youtube.com/kingbikerhead check it out and let me know what you think.

And as far as performance you loose a lil in bottom end but you gain a lot on top end and trust me it feels good to smash on the pedal and actually keep on goin at higher rpm's.

I mean its up to you from where you want to take I agree with it i love so yeah.

Go to the link and you'll see pictures of the way I have the exhaust done on my car and my friends car, and the iroc is myfriends and he has 3inch pipeing.

http://viewmorepics.myspace.com/inde...albumId=758908

Tony.

Last edited by DeathMetalTony; 10-06-2009 at 02:58 PM.
Old 10-06-2009, 02:58 PM
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Re: What are the downsides of dumping exhaust before rear axle?

Originally Posted by vanillagorilla
If you drive or park in a gravel, or dusty area (pits at the track, etc) it's gunna blow a lotta dust up. Mine have always been turned down and out before the axle, and i don't mind it...just be aware that if your beside others when you start it up, or move, they may get pissed if your blowing dust all over their junk. + side is during burnouts, it blows the tire smoke out and makes it groovy lookin! ...LOLOL
Yeah about that its true about the dust and gravel flying everywhere but hey you need to sacrafice sometimes.

Tony.
Old 10-07-2009, 01:39 PM
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Re: What are the downsides of dumping exhaust before rear axle?

Originally Posted by 84 z28
My car is setup like the blue camaro pictured but my exhaust dumps on each side right brfore the rear tires. If you do go that route you muffler choices are limited and usally have to go with racing mufflers.
The tire warmer exhaust!

A buddy of mines 70 chevelle is setup with the exhaust dumping in front of the tire. Looks and sounds great. Although there is 10x the room under his car than a 3rd gen has.
Old 10-07-2009, 05:21 PM
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Re: What are the downsides of dumping exhaust before rear axle?

I did the dual side exhaust set up on my car and all i can say is get a good muffler i use to have a single 3" into duals out the back with two glass packs and shorty headers and it sounded good but then when i went to the side exhaust with 3" tubing and long tubes with the same glass packs it was way to loud. when i get back from school in the summer im going to change it.
Attached Thumbnails What are the downsides of dumping exhaust before rear axle?-100_0966.jpg   What are the downsides of dumping exhaust before rear axle?-100_0963.jpg  
Old 01-03-2017, 02:53 PM
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Re: What are the downsides of dumping exhaust before rear axle?

I own a 5th gen camaro and I plan on adding some cherry bombs under car and a turn pointing out of side because right now I'm just dumping straight out of cat and its ridiculous but it sounds so good.
Old 01-03-2017, 02:56 PM
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Re: What are the downsides of dumping exhaust before rear axle?

Originally Posted by Daniel6210
I own a 5th gen camaro and I plan on adding some cherry bombs under car and a turn pointing out of side because right now I'm just dumping straight out of cat and its ridiculous but it sounds so good.

Old 01-03-2017, 05:31 PM
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Re: What are the downsides of dumping exhaust before rear axle?

You could dynamat the interior of the car, but dynamat is expensive so i bought aluminum backed window flashing for houses and did my rood and rear trunk panel(behind tail lights) to keep the heat out(roof) and try to bound my sub sound more to the front instead of out the back, one day i might do more of the car but who knows. Dynamat and its equivalents are also heat barriers too! But beware once they are put on, they give more h*** than anything you could imagine when trying to take off
Old 01-03-2017, 08:21 PM
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Re: What are the downsides of dumping exhaust before rear axle?

I'm running long tube headers, dual exhaust, with FlowMaster Super 10s, that dump just in front of the rear axle, with tips that are turned down and slightly outward. I don't find it too loud to have normal conversations inside the car with and it sounds great. The only down side to me, and it's been covered, is the dust it blows up in a dusty parking lot at times. Here is a video I took recently of a quick drive to the store with the windows down; it's much quieter with the windows up.



Old 01-03-2017, 08:25 PM
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Re: What are the downsides of dumping exhaust before rear axle?

Here is what it sounds like from the outside................

Old 01-03-2017, 08:42 PM
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Re: What are the downsides of dumping exhaust before rear axle?

Originally Posted by MSgt Luttrell
I'm running long tube headers, dual exhaust, with FlowMaster Super 10s, that dump just in front of the rear axle, with tips that are turned down and slightly outward. I don't find it too loud to have normal conversations inside the car with and it sounds great. The only down side to me, and it's been covered, is the dust it blows up in a dusty parking lot at times. Here is a video I took recently of a quick drive to the store with the windows down; it's much quieter with the windows up.



https://www.youtube.com/watch?v=zYBsv5KwhNU
Is that a RAII hood(like my signature pic) if so can i see some more pictures of the car?
Old 01-03-2017, 09:01 PM
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Re: What are the downsides of dumping exhaust before rear axle?

Originally Posted by ThirdGen1984
Is that a RAII hood(like my signature pic) if so can i see some more pictures of the car?









Old 01-04-2017, 05:52 AM
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Re: What are the downsides of dumping exhaust before rear axle?

Originally Posted by MSgt Luttrell








Beautiful car! Thank you! Pretty close to mine, of course mine is a 6 banger and not an iroc.... for now XD XD
Old 01-04-2017, 08:00 AM
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Re: What are the downsides of dumping exhaust before rear axle?

^^^Thanks, it's still a work in progress, but it's almost finished.
Old 01-04-2017, 11:53 AM
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Re: What are the downsides of dumping exhaust before rear axle?

Good afternoon MSgt Luttrell ,

Do you have no vehicle safety inspection in Arkansas ? I ask because where I live our cars have no emissions inspection whatsoever but we do still have a safety inspection and one of the big things they bitch about is the exhaust . Namely , that it can't be at all loud and that it has to run to the back of the car and not terminate anywhere under the car or in front of the rear wheels because that's not "as built" .

In other words , consider yourself lucky that Arkansas is as permissive as they seem to be about exhaust modifications because I'd never get my car past an inspection if I had an exhaust such as you describe .
Old 01-04-2017, 01:40 PM
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Re: What are the downsides of dumping exhaust before rear axle?

Originally Posted by OrangeBird
Good afternoon MSgt Luttrell ,

Do you have no vehicle safety inspection in Arkansas ? I ask because where I live our cars have no emissions inspection whatsoever but we do still have a safety inspection and one of the big things they bitch about is the exhaust . Namely , that it can't be at all loud and that it has to run to the back of the car and not terminate anywhere under the car or in front of the rear wheels because that's not "as built" .

In other words , consider yourself lucky that Arkansas is as permissive as they seem to be about exhaust modifications because I'd never get my car past an inspection if I had an exhaust such as you describe .
The state of Arkansas does not have any state emissions or safety inspections, that said they can stop you and do a safety inspection ticket on any gross safety violations. How gross it would have to be is anyone's guess, I've never seen anyone in the state get pulled over and written any violations for safety other than industrial trucks or if you are operating a vehicle with lights inoperative. I'm sure I could go get an excessive noise ticket somewhere in the state if I tried, but a little common sense goes a long ways.

Back when I was in the military and was stationed in Utah for four years, I legally kept Arkansas plates on my '67 Camaro and it drove the police there nuts; I got pulled over all the time for having a non factory hood scoop, but it was perfectly legal in Arkansas so they couldn't write me up for it. I got to know the officers in that town pretty well.


Last edited by MSgt Luttrell; 01-04-2017 at 01:45 PM.
Old 01-05-2017, 10:21 AM
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Re: What are the downsides of dumping exhaust before rear axle?

Two things , first that's great that Arkansas is less strict than where i live , and second , Damn we really had some fine looking cars available back in the day . My all time best wasn't a GM , it was a (real) 1970 Road Runner with the 440 sixpack & 4 on the floor .

That sure is one fine looking Camaro !
Old 01-05-2017, 04:43 PM
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Re: What are the downsides of dumping exhaust before rear axle?

Originally Posted by OrangeBird
Two things , first that's great that Arkansas is less strict than where i live , and second , Damn we really had some fine looking cars available back in the day . My all time best wasn't a GM , it was a (real) 1970 Road Runner with the 440 sixpack & 4 on the floor .

That sure is one fine looking Camaro !
Thanks, one of my buddy's back in the day had a 1970 440 six pack Challenger, a great car and he still has it. The latest build on the 440 is a 671 blower and dual four set up though.


Old 01-26-2017, 10:33 PM
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Re: What are the downsides of dumping exhaust before rear axle?

Seriously?!? Pulled over for a "non-factory hood scoop"?!?!? What kind of retarrr... idiotic, moronic, nonsensical laws do they have up in Utah??? That's just DUMB
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