batboy

iTrader: (6)

Any hints how to install a ZZP downpipe? I can't seem to find a removal guide. Does this sound about right? Put the car on jack stands. Disconnect the O2 sensor. Unbolt the front bolts and rear bolts. If the bolts aren't rusted, it should be fairly easy, right?

baltsk8er69

iTrader: (1)

That about sums it up. I used 2 12inch extensions to get to the 3 bolts that connect the rear manifold. If they're rusted get some pb nutblaster and let it soak for a few minutes. Get a new set of gaskets or you will be in there again. When tightening down the bolts do it like a tire. A little on one side a little in the other so it tightens evenly.

batboy

iTrader: (6)

Thanks. I haven't ordered the parts yet, but I will get new gaskets when I do. I'm still up in the air about cat or catless (no inspections here so I could go either way).

Next question, the exhaust is a little louder after you swap in a ZZP downpipe, right? How noticeable? I want a little more growl and rumble, but I don't want loud.

baltsk8er69

iTrader: (1)

I've had both...catless made the biggest difference in sound and power. You will regret going with catted. Unless your a tree hugger.

severs

No inspections here either but I wouldn't go catless. I live in the city and drive my Impala every day. All it takes is one grumpy cop smelling your butt, and it's a huge fine, maybe get your car impounded. Not worth the risk imo. At least use a fake one, or get a high flow cat

baltsk8er69

iTrader: (1)

Mine never smells so I'm not sure if that would be an issue for you.

07MCSS

iTrader: (3)

I'm catless and I don't care for the smell. It's fun annoying people at drive through windows though.

08GXPGXP

Not sure if u will have this problem but when I got mine the rear bolt location had to be grided out a little or the opening of the pipe wont align right. I dunno that's what I had to do.. The hole the bolt goes through needs grinned out a bit so the bolt can go a little further out to bolt up right.. Easy fix will the right drill bit.. I have a GXP btw lol

batboy

iTrader: (6)

Thanks for the advice, Mr. 08GXPGXP.

I was partway under the car yesterday and it looks like the front downpipe bolts are a little hard to reach.

baltsk8er69

iTrader: (1)

I'm quoting my self because I explained how to get the top manifold bolts.

straitchev

what kind of performance gains can you expect with this upgrade?

baltsk8er69

iTrader: (1)

Your probably looking at around 15-20 wheel horsepower. The stick pipe necks down to around under 2 inches. And the deletion of the cat gets rid of the rest of the restriction. You will need a tune to get the most of an improvement.

straitchev

Sounds like another weekend project. Anyone have zzp part #?

baltsk8er69

iTrader: (1)

I can get mine on and off in 20 mins

batboy

iTrader: (6)

ZZP says the downpipe is shipped. I ordered the stainless steel one with the high flow cat plus gaskets. I also ordered the square poly upper engine mount bushing. Not sure what I'm going to do about the intake yet. Might just leave the stock box or do some minor tweaks. If I get a new smooth 45 degree silicone elbow (TB to MAF), what are people doing about the PCV hose/fitting?

baltsk8er69

iTrader: (1)

I just poked a hole and shoved the barbed plastic fitting through. Careful not to poke too large of a hole. The fitting pops right out of the stock hole. Its been fine for about 40000 miles and numerous track passes.

baltsk8er69

iTrader: (1)

I used this elbow by shortening each side by a few inches with a razor till it was perfect.

http://item.mobileweb.ebay.com/viewi...id=47910818386

batboy

iTrader: (6)

So, you used a 3.5" diameter hose? I read in another thread that 3" was too small and 3.5" was too big. Supposedly a 3.25" is what fits perfectly.

baltsk8er69

iTrader: (1)

It worked fine. I think the elbow was a little tighter. I'm just speaking from experience that that exact elbow works awesome.

JonnyBuell

Does anyone have a pic of the stock u-bend pipe? I bought my car used and I'm not seeing the u-bend in my downpipe.