Possibly silly question but does eliminating the U-bend make much difference?
The reason I ask is that the lady I bought my GP from was told by the dealer's service department that she needed a new cat.
She had a new one installed, not sure where, and it looks like they replaced the downpipe as well and it doesn't have the U-Bend.
Will this have any noticable effects on the way the car runs and will it have any adverse effects on a completely stock engine?
Another question, is the can behind the cat a muffler or resonator and is it supposed to be about 5 inches in diameter and about 2.5 to 3 feet long?
I don't know what the stock exhaust looks like on one of these and this one just looks a little odd.
Thanks in advance.

Jim

Removing the ubend will decrease exhaust restriction, and provide a noticeable difference in power. Not anything neck snapping but you can feel it. Also the can behind the cat is a resignator.

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Thanks for the response, just curious really, when I crawled under the car before I bought it I saw that the cat had been replaced.
I asked the lady about it and she told me the dealer told her it needed to be replaced.
The car came with a stack of service records where she'd been taking it back to the dealer to have everything done to it, including routine stuff like oil changes since the car was new.
There are a fair number of 03' and below running around here and mine doesn't really sound like them.
Nothing glaring but it seems to have a deeper sound to the exhaust.
Thanks again for the reply, I'm slowly learning about this car.
Last GP I had was a 73' model with a 455 HO so this one is a whole nother animal.

Jim

I will dig up some pics and post them later and you will see how / why it makes a difference. And everything else sounds stock to me.



Stock dp




The bend in the stock pipe



Modified stock




Full 3"





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2001 white gt coupe with enough crap to make it run mid 13's with 3 bad pistons
2002 40th GTP sedan mostly stock

Thanks for posting the pics and mine still has the bend.
I screwed up, I saw another pic of a downpipe that had an odd bend at the bottom where it turns to go to the cat and assumed that was the U-Bend.
I does however look like they replaced the downpipe when they replaced the cat though since it's very, very clean with a minimum of rust and discoloration.
If I do at some point get rid of the bend, will I have to get rid of the rear O2 sensor or can the replacement be turned in such a way as to keep it?
We don't have emission inspections here as of now but you never can tell when they might start.
Also, I don't know of any place around here that does any custom tuning that could take the O2 sensor out of the system to keep an error from coming up.
Thanks again for the answers.

Jim

you would be lookin for one of these



that you can buy here.. (is same as what i have pictured)


http://shop.zzperformance.com/store/p/2 ... elete.aspx

-- Mon Jan 30, 2012 2:33 pm --

it has a spot for the O2 and if you dont want to run one, then you just leave the plug in it..

it can be tuned out or run an O2 simulator also/insted. if no rear O2 is desired.

the ubend you are thinkin of is at the front of the down pipe on the speed daddy style headers and removing that would have some gain too, but the headers are so much better than the stock manifolds that it is minimal over the total header swap

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2001 white gt coupe with enough crap to make it run mid 13's with 3 bad pistons
2002 40th GTP sedan mostly stock

Thanks for the link bigdog, I'll definately look into getting rid of the bend.

Jim

no problem, why we are here.. you could look for a used one.. hint.. hint.. . sometimes ppl by one then go headers and dont need it or whatever.. so they could be had for a little cheaper than new too.

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2001 white gt coupe with enough crap to make it run mid 13's with 3 bad pistons
2002 40th GTP sedan mostly stock

LOL! I'll definately check around (wink wink nudge nudge) for a used one, but it'll be after I get the engine back together.
I'll post about that in a bit, I suspect bad karma may have bitten me in the butt again.

Jim