Why are the connecting pies " s shaped"

[birdbrain]

So the stock connecting pipes from the rear exhaust are really curvey like 2 big "s" shapes. I notice a lot of aftermarket systems do not deviate from this.

Why however is there not just a straight pipe or straighter pipe without all the bends. I would think gas velocity would be faster through less turns and twists. I can see for a stock system to slow the gases down and thus be quiet but why are aftermarket companies not addressing this.

I know for years exhausts would focus on providing a better direct pathway for the gases to flow. I cant see the curviness has any benefit??

[JCtx]

Pipes need to clear suspension components and half shafts, so they have to be close to the differential. Problem is the stock exhaust has the muffler inlets all the way to the edges, hence that routing. But most importantly, a properly (Mandrell) bent pipe flows basically the same. Plus you have much more radical bends inside the muffler anyway .

[Krozi]

The diff is in the way.

[Singletrack]

Originally Posted by birdbrain

So the stock connecting pipes from the rear exhaust are really curvey like 2 big "s" shapes. I notice a lot of aftermarket systems do not deviate from this.

Why however is there not just a straight pipe or straighter pipe without all the bends. I would think gas velocity would be faster through less turns and twists. I can see for a stock system to slow the gases down and thus be quiet but why are aftermarket companies not addressing this.

I know for years exhausts would focus on providing a better direct pathway for the gases to flow. I cant see the curviness has any benefit??

I've always thought it was to give the diff some breathing room. Don't really want to super-heat that bad boy with two pipes directly next to it and running the length of the housing.

[aajami]

Here's a quick and dirty image I created to help illustrate why those twists and turns are necessary (other than just looking cool):



The first bend is to clear the rear differential.
The second bend is to clear the camber link.
The final bend is to line up with the exhaust canister.

[jmflukeiii]

Originally Posted by Krozi

The diff is in the way.

winning

[birdbrain]

I get that but if you look at the pictue above you could aslo draw a "straight" line through the middle of all the "s curves" and you would clear everything as well. I have seen that in many other cars where aftermarket essentially removes most of the bends in their aftermarket stuff. I really think it is more about slowing exhaust gas down then avoiding stuff. I mean yes it has to avoid certain things and cant be perfectly straight through but you could essentially have a very gradual straight curve fit in that same area with no issue looking at the picture.

The S of the curve actualy looks like it is RIGHT against the diff whereas a straight one could avoid that based on the pick if you picture a straight one through the center of all the middle points of the S curves

[rzm3]

OE pipes are also designed to keep heat away from some of the components.

[alpine335i]

Could you remove bend 1 and 2 and go right next to the diff but wrap the piping with header heat wrap?

[donovan]

Cool thread, interesting.

[birdbrain]

Originally Posted by rldzhao

OE pipes are also designed to keep heat away from some of the components.

That is the point, didnt you look at the picture above? My whole point is the current S setup makes the exhaust pipe almost touching the differential-now how is that good as far as heat goes? A straighter pipe would be MUCH further from the componenets than the S shape now-just look at the picture and draw a straight line connecting the pipes to the mufflers instead of the S-pipe.

[Chill72]

Originally Posted by birdbrain

That is the point, didnt you look at the picture above? My whole point is the current S setup makes the exhaust pipe almost touching the differential-now how is that good as far as heat goes? A straighter pipe would be MUCH further from the componenets than the S shape now-just look at the picture and draw a straight line connecting the pipes to the mufflers instead of the S-pipe.

You also got to think about "cut outs" and mounting points for the S-shape pipe. To put in a stright pipe you would need new mounting points at least so aftermarket manufacturers probably don't feel like messing with all of that so they leave the S shape like the stock configuration.

[Ryan@IND]

not all designs follow that convention. Here is the bastuck with a much straighter piping design.

[dcgolfdr]

+1 on the Bastuck, I have had it on the car for 2 years, clears everything

[NDAPUPR]

I think what the OP is trying to say/ask, what is gained by keeping the S curves? Straight pipes are definitely possible since there is already a manufacturer who does it, but why do most manufacturers keep the curves? I too would believe there is certain reasoning behind that might of been found during R&D.

[NDAPUPR]

Or alternately like this. That last pic probably wasn't the greatest.