Q & A : Exhaust

[jonny-rockets]

What is the different between headers & an exhaust manifold? Or are they the same thing?

[Robk0000]

Same thing. (Just kidding)


Sidenote: Egt probe, do they have to be welded in or can they be tapped intot he exhaust. Also, where is the optimal location, on the dp next to the turbo?

[Nick S.]

Same thing.

Actually not the same thing

-A manifold are usually a cast peice where all the exhaust ports in the head flow into the same space inside the manifold before the collector. And the runners are not equal lenght.

http://img.alibaba.com/photo/11494968/Exhaust_Manifold.jpg

Headers are tubular, each runner is usually divided from the other runners until the collector. Usually they are designed to have the same length for each runner for better flow but not always.

http://www.kenrockwell.com/bmw/images/m3-2007/headers-784.jpg

Sidenote: Egt probe, do they have to be welded in or can they be tapped intot he exhaust. Also, where is the optimal location, on the dp next to the turbo?Usually if the manifold is cast you can just drill and tap a whole in the manifold a couple inches downstream of the head in the #1 cylinder runner.

Here is a picture of one on a subaru.

http://i2.photobucket.com/albums/y48/dtech114/2006%20STi/Gauge%20Install/EGTsensorinstalled.jpg

Here is another more clear picture.

http://www.turbododge.com/dodge_pictures/files/9/3/3/3/turbo6.JPG

[Robk0000]

What about on a diesel truck, turbo obviously. Those headers above look really purrty.

[jonny-rockets]

perfect explanation thanks!

[kgj996]

Once again Nick saves the day! you should put a tubular header on your car! I bet it would add tons of power.:lol:

[banned4life]

Same thing. (Just kidding)


Sidenote: Egt probe, do they have to be welded in or can they be tapped intot he exhaust. Also, where is the optimal location, on the dp next to the turbo?


my egt is in my exhaust manifold. drilled and threaded

just like this

http://i2.photobucket.com/albums/y48/dtech114/2006%20STi/Gauge%20Install/EGTsensorinstalled.jpg

[Robk0000]

i know how to do it, i just am not sure if it goes on the DP or up pipe on a turbo car

[Kevin]

I think a wideband afr would go in the dp. not too sure though

[kgj996]

the wide band should go post turbo because the high pressures pre turbo through the readings off.

[Robk0000]

not afr, the egt probe.

[pjk91]

best guess? 6-12" after the turbo in the exhaust stream. am i right? not sure.

[Jon]

The egt probe should go in the exhaust manifold pretty close to where it exits the motor. Look at the pic eb50 posted. There is a specific cylinder # that you should put it into with the wrx because it sees the hottest temps, but i don't recall what it is. I'm not sure if it matters which one you choose with the rs.