ZZP DOWNPIPE on 2005 GTP

[lawadm1]

I'm wanting to get the ZZP Downpipe for 2005 GTP, and I want to make sure I get everything that I need. There are 3 options to choose from. 3 inches, 2.5 inches, and 3 inches with 3 inch outlet. If I'm attaching this to everything else stock, which one do I select? Do I need gaskets for each end? And then there's mention of the O2 sensor extension. Do I need this as well?

I'm starting there, but will most likely get the Plog also at a later date.

Is there anything else that I'm forgetting?

TIA

Jeff

[digitaloutsider]

Pretty sure the item description tells you exactly what to buy.

All bolt in downpipes have a 2.5" exit flange that bolts in the factory location, if you would like a 3" exit flange please attach a $20 custom payment to your downpipe order and we will include the correct bolt in flange.

2.5 inch downpipes are designed for naturally aspirated applications where no loss in low end torque is desired.

04+ Grand Prix' will require a style "B" o2 extension for the rear o2 sensor.

Most common downpipe gaskets can be found here: exhaust manifold to downpipe inlet gasket, downpipe to factory catback/2.5" catback gasket.

[Fivefingerdeathpunch]

Get the 3in downpipe with regular outlet size.

[lawadm1]

Thanks all. Sorry, I guess I skipped over the product description and went right to the reviews. I think I have what I need now.

One last thing...How hard is it to get to the front DP bolts from the engine bay? I understand the tools needed are: 6pt 13mm and 14mm deep sockets, 10-12in extension, socket swivel, and some penetrating oil. Does that sound about right?

[Fivefingerdeathpunch]

Everything is done from under the car, pretty straight forward.

You'd really have no room to move your wrench from up in the engine bay.

[digitaloutsider]

A day before you plan to install it I'd get the bolts soaked in some Deep Creep to help break them loose. Like FFDP said, you cannot get at them from the engine bay. You need the car jacked up and be under it. An impact would make very short work of them, but if you don't have one, get up under there with a breaker bar and some extensions.

[GTPpower]

I use an impact, swivel, and about 2 ft of extensions.

[99GT2dr]

The DP to catback bolts on my '04 were 15mm.

[Pursell1911]

Have fun, just installed mine a few days ago! I used PB Blaster and let the bolts soak for about 24 hours. It was suggested to me to start the car for a few minutes to let the bolts securing the pipe to the engine heat up, which helped me. I had to hold the exhaust with my foot and kick the wrench to get the back bolts loosened.