: Why the hell did the factory squish the exhaust pipes in the center?



Moparman4444
07-08-13, 12:15 AM
I looked under my coupe and saw that the factory crushed the 2 1/2" exhaust tubes down to 1"x3 1/2" in the center of the car. Seriously?? Why the hell would anyone do that? Does it reduce noise, air flow, limit power? What?

There is plenty of ground clearance and smashed tubes make no sense to me.

Can anybody explain??

cruiser68
07-08-13, 12:45 AM
They pretty much all have it. One of the many reasons I went headers. I know some have fixed it. I also know of 700+HP on stock exhaust so it flows decent if you fix the kink....and remove or replace the cats.

Trapspeed
07-08-13, 10:10 AM
For all we know they're using the same Y-pipe that was used on the old Camaros. The one on my '99 SS had the same crimp....until the headers went on! :D

wait4me
07-08-13, 01:10 PM
It allowed for machine robot easy installation onto the vehicle.

spearfish25
07-08-13, 01:30 PM
The area through the squished portion may still be the same as the unsquished part. Just a different shape.

cruiser68
07-08-13, 01:46 PM
Having looked at it up close I would guess there is 50% of the original cross section left through the crimp.

Da V-Man
07-08-13, 02:06 PM
If the crimped pipe measures 1x3.5", like the OP's pipe, then the cross-sectional area is about 35% smaller than the round pipe. If the crimped pipe measures 1.5x3", like my pipe, then the cross-sectional area is about 20% smaller than the round pipe.

DiamondWhtV
07-08-13, 02:09 PM
Doubt you will ever get a true answer and just a bunch of guesses. My guess that it had to do with either manufacturering or assembly requirements. Regardless it probably has no effect on a stock engine. If you are going to add a bunch of horsepower, you would go the route of headers and eliminate any flow restrictions. I can think of a few silly things they did to the V- like no spare tire, that are more important.

Trapspeed
07-08-13, 02:24 PM
On the Camaro, I can almost cite a ground clearance issue. With the off road pipe it would grind a speed bump if I wasn't careful.

gaduser
11-13-13, 04:44 PM
My 2011 Coupe has a similar "smashed pipe". It is hard to believe that GM would accept what appears to be shoddy workmanship and/or damage prior to delivery.

Might the "smash" be a factory adjustment, albeit crude. It may be that the power system is unbalanced, left to right, either forward and/or aft of the "smash". I believe it possible that a crimp might provide some flow and/or pressure balance. Further, it may have to do with the acoustics of scavenging. One might generously call it a crimp in one of those or similar cases. Note that the air intake is not centered which may contribute to some form of asymmetry in function of the system. The blower certainly can favor one bank and/or some cylinders.

I began to wonder after seeing several pipes. They were not all the same. One should expect that if the right side can be bent smoothly, so can the left. It does not look like a virgin manufactured component.

If my postulate is correct, good for GM for making the adjustment even though is seems a little crude. If not, ...............

Arca500
11-15-13, 08:52 PM
Wait4me hit the nail on the head. I've seen this in many different GM vehicles over the years. Even on a 94 GMC turbo diesel dually. It's just for easy manufacturing. That's all.

dennych
11-16-13, 05:02 AM
Mechanic claimed it is better for torque #'s at the cost of a few HP.

Moparman4444
11-21-13, 09:06 AM
I would guess its to limit performance upgrades by restricting flow.

Da V-Man
11-21-13, 01:42 PM
you guys are overthinking this. Look at the pipe locations under the car. On the passenger side there is more overhead clearance, and the pipe is installed a little higher. On the driver side there is less overhead clearance, and the pipe is installed a little lower. The pipe had to be squished to meet minimun ground clearance requirements.

Trapspeed
11-21-13, 01:56 PM
you guys are overthinking this. Look at the pipe locations under the car. On the passenger side there is more overhead clearance, and the pipe is installed a little higher. On the driver side there is less overhead clearance, and the pipe is installed a little lower. The pipe had to be squished to meet minimun ground clearance requirements.

Exactly.

thebigjimsho
11-21-13, 07:00 PM
It's a conspiracy!

gaduser
11-23-13, 06:45 PM
Good thing the mirrors don't stick out too far.