I would have just as soon researched the entire site, but us here in CA are a little bit more observational when buying a exhaust system due to our terrible emissions laws. Keeping those laws in mind, and not (just for the heck of it), what set up is better than another? HKS, Invidia, GReddy, etc.? This is gonna be the first thing I'm looking into on the Z. Thanks.

 

well emissions isnt the main thing cops pull you over for.
most catback systems and even y-pipe's do not affect pollution that much to the extent of being a gross polluter.

With exhausts. your main concern is noise. Anything like a fujitsubo where it is a full muffler is fine. Exhausts like the RS*R GT2 may be a little tooo loud and cause too much attention from cops

 

+1

 

+2

 

+3 for the most part.

The rules state that factory cats must be retained and in the same location, anything after the factory cats can be changed, as far as emission laws go.

Technically, the Greddy system, because it relocates the evap canister (or some such) is illegal but chance of even the smog tech hassling you are slim as long as everything is connected and working.

I believe all three systems you listed are below the 95db CA limit.

Chris

 

True Dual's (Borla, HKS, Injen, etc) tend to be more throaty, single pipes (Nismo, Fujitsubo, etc.) tend to retain the sound of a VQ and dual canister's (Apex'i N1, Topspeed, etc) tend to be slightly higher pitched and louder than the other two types. These are generalities, there are exceptions.

Of course when you start adding headers, HFC's or test pipes, the equation changes.

The best thing to do is try and listen to a few in person before deciding which one you want. (Take it from a guy who has had three different exhausts on his car.) Or you can look in the exhaust section and find plenty of sound clips.

 

Very true. You can have 2 guys with the same exhaust system but one may sound a bit different due to additional mods. I'd definitely take the opportunity to listen to a few local memeber's exhaust systems before you decide. Also, don't just people's word for it since the sound itself is very subjective & videos/sound clips will distort the sound. What may sound good to one person may not sound good to you.

 

Very true, thank you all for your input. I'm sure that through this I can make a justified decission. Thanks.

 

I found for value and hp gains, you cannot beat the Borla system, and it is pretty easy to install yourself. It sounds deep, almost like a muscle car. The problem I found with it is that because of the extra air flow (especially with an intake) your car will run lean, which can actually reduce hp (this is probably true with all of the systems). This can easily be corrected with an ECU upgrade or maybe even a simple tune up. If all you want is sound, then the injen and gretty sound more like a tuned sports car, rather then a muscle car. Also, if you are looking for TD (true dual) exhaust, do some research about H-pipes vs. X-pipes. X-pipes seem to cause less turbulence, allowing for better flow. the borla system is a H-pipe system, while the Stillen system has an X-pipe. Some TD systems have neither, which can cause pressure differences between left and right cylinders, causing hp loss, rough idle, slower throttle response among other small problems. Then agian, it might work perfect for your car.

 

hmmm, interesting...

 

Exhaust and intake will not make your car lean.

 

Tanable supposively came out with a whole new line of exhaust exclusively for under 93 db and smog test certified with good power gains. If intrested you should look into Tanable exhausts.

 

aye i'm new here guys but I wonder if the db test the manufacturers do are the same as what the state ref does.

our shipper, gilbert, got a state ref... they were did a 45 deg angle like 18" away, instead of what people think is like 10 feet away.

our local evo forums has a listing of all the exhaust w/ db reading, but again, it was done not 18" away, rather 10 feet away.

I just got my Z a few days ago... did the wheels/tires/eibachs... now i'm actually looking 4 an exhaust.

sd