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?

 

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.

 

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.

 

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

 

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

 

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

 

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

 

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

 

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.

 

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

 

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

 

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.

 

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

 

I can get mine on and off in 20 mins

 

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?

 

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.

 

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

 

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.

 

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

 

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.