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-   -   exhaust question (https://67-72chevytrucks.com/vboard/showthread.php?t=291893)

jdurant 05-15-2008 11:06 PM

exhaust question
 
Right now my Blaxer has a single flowmaster with a dump for exhaust. Sounds good, everything is fine until I roll all three windows down. Then I get a whole lot of exhaust fumes circulating through the truck. Since it is no good dumped, I guess, I would like it dual and coming out at 45s between the rear bumper and tire. I'm not sure if there is enough room to make that look right with the fuel tank.
Let me know what you guys have done.
Thanks. pics would help.

GG_Blaisdell 05-16-2008 02:59 AM

Re: exhaust question
 
I also like the idea of the 45 degree pipes at the rear. Saw a Ranger with a nice dual set-up like that and think it would compliment the Blazer well. I wonder if the quasi-out the back location would cause any problems with the read window rolled down? Anyone have ideas or experience with something like this?

kevinr1970 05-16-2008 03:05 AM

Re: exhaust question
 
Quote:

Originally Posted by jdurant (Post 2723575)
Right now my Blaxer has a single flowmaster with a dump for exhaust. Sounds good, everything is fine until I roll all three windows down. Then I get a whole lot of exhaust fumes circulating through the truck. Since it is no good dumped, I guess, I would like it dual and coming out at 45s between the rear bumper and tire. I'm not sure if there is enough room to make that look right with the fuel tank.
Let me know what you guys have done.
Thanks. pics would help.

Heres the way I understand it to work.
With all three windows down, when the air passes over the door windows it creates a vacuum. The vacuum pulls air IN through the rear window and it gets sucked out the door windows.
So regardless of where the exhaust is located it will still get exhaust as the exhaust swirls around behind the truck when moving. Thats why the back windows get so dirty.
Conversely, if you keep the door windows shut but have the rear window down and then open your floor vents (non-AC trucks) or set your HVAC control to "vent" it will provide massive amounts of air.

In theory...

68Timber 05-16-2008 05:21 AM

Re: exhaust question
 
My last Blazer was 45'd on each side, that's how I plan to do this one. It looks good and there's enough room to do it.

tobiahr 05-16-2008 04:26 PM

Re: exhaust question
 
If you are trying to keep exhaust from coming in you have to keep the rear window shut. I've had both the the 45 degree pipes, rear dumps (came out beside the license plate) and even a set of side pipes that dumped in front of the rear tire. With all of these i still had problems with exaust fumes with the rear window down and strangely enough problems with the top off with the rear dumps. I have also had fume problems with leaking weatherstripping on the rear gate with rear dumps. Currently going with 45 degree pipes to avoid as much as possible. IMHO they look better too.

tvblazer78 05-16-2008 06:04 PM

Re: exhaust question
 
Quote:

Originally Posted by tobiahr (Post 2724769)
If you are trying to keep exhaust from coming in you have to keep the rear window shut. I've had both the the 45 degree pipes, rear dumps (came out beside the license plate) and even a set of side pipes that dumped in front of the rear tire. With all of these i still had problems with exaust fumes with the rear window down and strangely enough problems with the top off with the rear dumps. I have also had fume problems with leaking weatherstripping on the rear gate with rear dumps. Currently going with 45 degree pipes to avoid as much as possible. IMHO they look better too.


All of this is all right, if you run it in front of the back tire and have the top off it works well. That is just how the blazers are...

jdurant 05-16-2008 09:16 PM

Re: exhaust question
 
That is what I was afraid of. That really sucks, since one of the best percs of the Blazer is to ride with all three windows down--the circulation is perfect and the turbulance is low, you can still hear your stereo really well. I guess I will see if it is any better with 45s when I get around to it.

tobiahr 05-16-2008 09:32 PM

Re: exhaust question
 
its ok though...after a while with the window down you get kinda sleepy and the smell doesn't seem to bother you as much ;)

Kaysenmc 05-16-2008 10:16 PM

Re: exhaust question
 
My blazer Was dumped before the rear axle, and never noticed any fumes (window down, or top off). Now my exhaust runs straight out the back, and it can burn you out with that back glass down.

68Timber 05-17-2008 12:41 AM

Re: exhaust question
 
To me the best part of a Blazer is top off! The two I had previously, I eventually quit riding around with the back glass down but it had nothing to do with exhaust fumes. It sucks in dirt and I was constantly cleaning the inside of the top to get it white again on the interior.

jdurant 05-17-2008 02:08 AM

Re: exhaust question
 
I'm gonna install a giant air filter.

68Timber 05-17-2008 05:52 PM

Re: exhaust question
 
Quote:

Originally Posted by jdurant (Post 2725430)
I'm gonna install a giant air filter.


There you go. Big K&N cone on each exhaust tip. TRICK!

:)


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