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Old 08-08-2011, 10:23 AM   #1
blazer2007
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is it a no no to run exhaust out back

Wanting to quiet down the blazer ,the exhaust exits in front of the rear tire but I want to run it out to the back.I like the look or the exhaust coming straight back under the bumper but was wondering if the exhaust will come in thru the back window when down
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Old 08-08-2011, 12:27 PM   #2
blakeduren
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Re: is it a no no to run exhaust out back

YES! It will come in the back window when down. Even with all the windows down it can sneak in.
Angle it at 45 degrees out or 90 degrees out of the side.
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Old 08-08-2011, 03:55 PM   #3
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Re: is it a no no to run exhaust out back

thanks
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Old 08-08-2011, 05:14 PM   #4
thirdstreettito
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Re: is it a no no to run exhaust out back

Well, now. My 88 has a single 3" behind the drivers side rear tire and it comes in and I smell it, but only when off the gas. My 83 has dual 2.5" out at each rear corner and I can never smell it, even in the back seat, but people who ride in it say they smell it(I think thats BS).
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Old 08-10-2011, 01:48 AM   #5
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Re: is it a no no to run exhaust out back

I used to see K5s running around with tailpipes coming waaay out from behind the rear wheel and always thought it looked bad. I bet those guys never smelled exhaust. Guess what I'm thinking about doing?
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Old 08-10-2011, 12:57 PM   #6
OrrieG
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Re: is it a no no to run exhaust out back

You might look at some newer truck tips that let air go in and channel or increase the flow away from the truck. I have seen them on diesels I think for the same reasons, or it might be for noise reduction.
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Old 08-11-2011, 10:39 AM   #7
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Re: is it a no no to run exhaust out back

Quote:
Originally Posted by OrrieG View Post
You might look at some newer truck tips that let air go in and channel or increase the flow away from the truck. I have seen them on diesels I think for the same reasons, or it might be for noise reduction.
those tips, (ive heard them called intercooled) do alot to decrease exhaust temps at the tail pipe as well
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Old 08-11-2011, 10:58 AM   #8
thirdstreettito
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Re: is it a no no to run exhaust out back

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those tips, (ive heard them called intercooled) do alot to decrease exhaust temps at the tail pipe as well
Yes, but they create back pressure in the exhaust system. Back pressure drastically decreases the performance of a diesel engine. Gasoline engines needs back pressure in the exhaust to create vacuum. Diesel engines are compression engines, whereas gasoline engines are spark.
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Old 08-11-2011, 11:06 AM   #9
camshaftgsxr
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Re: is it a no no to run exhaust out back

Gasoline engines don't need back pressure, vacuum is created by the pistons trying to pukl in more air than the throttle body or carb/ cam will allow, these tips im talking about have slots around then to introdue fresh air into the tail pipe. I would run them in front of the rear tire to avoid the problem all together
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Old 08-11-2011, 10:38 PM   #10
motornut
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Re: is it a no no to run exhaust out back

mine are 90 out the sides
tried straight back with a barn door burb, was ok(pic), but the gate burb, no way.
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Old 08-11-2011, 10:42 PM   #11
Dalaigh
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Re: is it a no no to run exhaust out back

On a suburban or k5 with the gates, I vote against straight out back just because if your sitting in traffic with the window down, the fumes will get in the truck.
On another note, why is you exhaust so low motornut?
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Old 08-11-2011, 11:18 PM   #12
motornut
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Re: is it a no no to run exhaust out back

i think it's me taking the pic
but i did think that when i first got it and others ask too
but i think it would hit otherwise
but it was on it when i bought it,not sure
but i wana go out front of the wheels under the running boards
need a better pic tho
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Old 01-16-2012, 11:43 AM   #13
Dalaigh
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Re: is it a no no to run exhaust out back

I know its a little late to say, thats alot of but's
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