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Old 06-21-2008, 10:22 PM   #1
prg machine
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exhaust exit preference???

I was wondering what opinions there might be as far as the exit point for dual exhaust for performance, sound, etc. for the following:

old school hot rod style/ tail pipes dump straight down after exiting mufflers and dump underneath the bed....simple set up



side exit in front of rear wheels


traditional rear corner exit


also is there any real difference in the size of tail pipe after the mufflers??
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Old 06-21-2008, 10:50 PM   #2
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Re: exhaust exit preference???

My exit points have always been determined by the amount of work I want to do. My truck now has duals that turn out in front of the rear tires.. real easy. Now what I want to do is run them threw the rear crossmember and straight out the back.. but more cutting and fitting is involved along with more material.

Heres some good reading on exhaust
http://www.superchevy.com/technical/...exh/index.html
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Old 06-21-2008, 10:55 PM   #3
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Re: exhaust exit preference???

I always liked them either at a 90* bend and out behind the rear wheels or 45*s out behind the rear wheels,I like the echo with 3" or so angle tips tips when it echos off guardrails and buildings.
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Old 06-21-2008, 11:49 PM   #4
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Re: exhaust exit preference???

i prefer them to dump out infront of the axle
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Old 06-22-2008, 12:51 AM   #5
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Re: exhaust exit preference???

Side before tires is my preference..

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Old 06-22-2008, 02:41 AM   #6
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Re: exhaust exit preference???

Dump out just outta the muffler under the truck, before the axle.
It does stir up dust, but there are no tailpipes hanging out killing the look of the truck.
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Old 06-22-2008, 05:22 AM   #7
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Talking Re: exhaust exit preference???

[QUOTE=chevjayfsd;2775893]Side before tires is my preference..

It just sounds good when you rev it up next to someone's window here's a small clip of my single Exhaust idling!

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Old 06-22-2008, 06:40 AM   #8
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Re: exhaust exit preference???

Now that you mention it,..... on a truck I think the old school way in front of rear axle exhaust tips down, on my sub I like behind rear tires exit out the side, just because of possible fumes getting into interior,........ there was a 1970's car movie I remember part of, I think it was a purple 68 or something Road Runner, the guy had the exhaust piped into his interior, I think he got pulled over by the Law, he stumbled out laughing and opened the trunk, and a bunch of chickens jumped out.... something wierd like that.

but for performance, there has to be a '' Sweet spot '' for the length of exhaust, .... the right length for a specific engine for best HP and Mpg.
it is all in the back presssure somewhere I bet.

kent
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Old 06-22-2008, 08:04 AM   #9
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Re: exhaust exit preference???

Hidden IMO..i have never seen a way they exited that i liked..........
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Old 06-22-2008, 08:27 AM   #10
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Re: exhaust exit preference???

Just running out of the mufflers under the bed can cause an annoying rumble/resonance.

Angled in front of the rear tires is my choice, most of the time.
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Old 06-22-2008, 08:32 AM   #11
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Re: exhaust exit preference???

I like them run all the way out the rear.I just think it gives the truck a more balanced sound from the drivers seat where I spend most of my time while it's running.
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Old 06-22-2008, 08:51 AM   #12
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Re: exhaust exit preference???

I've always liked the look of them all the way out the back, with chrome/polished stainless tips. I'm thinking of going that route, but I am concerned about clearance when I take my truck out in the woods. Having all those bends to clear the axle probably doesn't help in terms flow/backpressure, either. Still, it's the "look" that I like.

As for performance, redhead69 has pointed you in the best direction, IMHO. I have been a big fan of David Vizard for his technical expertise (mainly because he backs up everything he says with dyno testing - not wild claims or estimates).

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Old 06-22-2008, 10:29 AM   #13
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Re: exhaust exit preference???

Quote:
Originally Posted by prairewolf View Post
Now that you mention it,..... on a truck I think the old school way in front of rear axle exhaust tips down, on my sub I like behind rear tires exit out the side, just because of possible fumes getting into interior,........ there was a 1970's car movie I remember part of, I think it was a purple 68 or something Road Runner, the guy had the exhaust piped into his interior, I think he got pulled over by the Law, he stumbled out laughing and opened the trunk, and a bunch of chickens jumped out.... something wierd like that.

but for performance, there has to be a '' Sweet spot '' for the length of exhaust, .... the right length for a specific engine for best HP and Mpg.
it is all in the back presssure somewhere I bet.

kent
Kent that scene may have been in the Eastwood movie Thunderbolt and Lightfoot. It sounds familiar.
And I think you can't go wrong with running the pipes out the back, either straight or angled down.
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Old 06-22-2008, 11:31 AM   #14
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Re: exhaust exit preference???

I like the hidden or "tucked" exhaust as well exiting behind the rear tires at 45 or 90 degree angle.
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Old 06-22-2008, 11:53 AM   #15
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Re: exhaust exit preference???

I like mine out the back. Exhaust isn't noise, its music.






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Old 06-22-2008, 01:23 PM   #16
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Re: exhaust exit preference???

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Old 06-22-2008, 03:29 PM   #17
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Re: exhaust exit preference???

I used to be one that would exit out past the back bumper...but here lately I have been liking it behind the tires.
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Old 06-22-2008, 07:19 PM   #18
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Re: exhaust exit preference???

I have mine turned down after the rear axle with 3 1/2" tips. I like it, the Thrush turbos dont rumble enough for me though.
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Old 06-22-2008, 10:11 PM   #19
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Re: exhaust exit preference???

Quote:
Originally Posted by bad6772 View Post
Hidden IMO..i have never seen a way they exited that i liked..........
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Old 06-22-2008, 10:23 PM   #20
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Re: exhaust exit preference???

empty behind the wheel. I had them straight back on an older blazer and with the top off I was sucking to much exhaust back into the tub.
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Old 06-22-2008, 10:25 PM   #21
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Re: exhaust exit preference???

I agree with above. Exit behind the rear wheels
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Old 06-22-2008, 10:26 PM   #22
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Re: exhaust exit preference???

I like mine out in front of the rear tires. It isn't under the bed to resonate, and it really isn't THAT loud, given mine is just glasspacks off of headers and 2 inch pipes.

It was simple, fairly straight forward and easy, and cheap. Which is what I was going for at the time, and would still go for. I have no regrets with the way it sounds, and have been complimented a couple times since apparently no one runs glasspacks anymore and it's "distinctive".

Oh, and you can't be running through a tunnel, punching the clutch, and blapping the throttle a couple times to have those tunes walk up the walls, haha.

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Old 06-22-2008, 10:36 PM   #23
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Re: exhaust exit preference???

i prefer turn downs after the before the axle. as long as you don't live down a dusty road. although it does look cool when you rev it up on a dusty road.
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Old 06-23-2008, 12:53 AM   #24
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Re: exhaust exit preference???

funny someone brought this up... I was just out in the garage today trying to figure out if/how/where i want my tail pipes to go. right now they are already over the axle and following the frame rail, but i never put the actual tail pipes on. Well, after dicking around with it for a few min, i think i'm gonna leave them as is. hidden under the bed, nothing sticking out.

it's a shame though. I kinda want to show off the work my uncle did getting them over the axle, and out the back, while working around bags, gas tank, air tank, compressor and shocks.
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Old 06-23-2008, 01:45 AM   #25
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Re: exhaust exit preference???

I have been a 4X4 guy all my life. So in front of the wheels, or behind the wheels ect. just collected mud, or got crushed on logs or rocks. I have always run exhaust straight out the back with 4"x24"or18" 45* cut chrome tips, I kept them slightly ahead of the rear bumper to keep them from being crushed on the departure angle, and about as wide as the reciever hitch frame.

I had an old caprice classic once, that exited just in front of the rear tires. That car always ran rich so it usualy had soot on my rear chrome reverse smoothies with baby moons. To fix that I put chrome turn down tips on it. Then later I rebuilt the carb.

Long winded responce cut short, I think I will go with sidepipes on my 67. Personal prefrence is what realy matters. Since I have always wanted a vehicle with suicide doors and side pipes, and I love 67-72 chevy pickups Im putting everything I like into this truck. I dont realy care if everyone likes it, as long as I like it, it dont matter what anyone else thinks.

Bottom line is no matter how you build a truck some people will love it and some people will hate it.
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