So i got these pipes this morning from [email protected]
I couldn't find any thread for these anywhere on any G/Z site, so I figured I'd make one.
The box was pretty small compared to my friend's down pipes. Anyhow, everything was packed very nicely and individually with bubble wrap to prevent scratches. The cats were marked "Driver Side" and "Passenger Side" to prevent confusion. Also included is a full hardware kit along with 4 thick gaskets and some decals. No instructions though (I don't think you can go wrong anyway). I also ordered O2 sensor extenders to prevent any CEL codes. We'll see how well they work out.
These pipes are really beautiful! The welds are really clean and the flanges are thick stuff. Since these are 200 cell cats, they should provide higher flow over most HFC's out there while still provide exhaust filtering ability. (I think most are in the 300 cell range. The higher the number, the less the flow).
First I'd like to apologize for the poor quality install pics. My hand was dirty and I was in a tight spot so i could barely click the button. Anyways, the total install time was exactly one hour including a 20 minute break in the beginning waiting for the engine to cool down and WD40 to work it's way into the bolts. The stock upper studs were so weak from all the heat that one of the heads just broke off with very little effort on the passenger side cat. Once the stock cats went out, we installed the Invidia studs and bolted them right up. fitment was very good with my Stillen cat back. Unfortunately, the sensors did not fit in the supplied anti-foulers. So for now we have them installed directly onto the cats and so far no CEL after about 25 miles of driving. I also took out the stock brace for the cats since it was sitting there doing nothing (I hate dead weight
). It is interesting to note how much lighter the Invidia cats were compared to stock. The stockers also look much more restrictive.
So far after 25 miles of driving (I went up to 125mph a couple times), I felt like I lost a very slight amount of torque at low RPMs. However, once the needle gets over 4,000RPM it's a whole different story. Definitely much more power up there. It just went at higher speeds at a much faster rate. I will comment more here once I get more mileage on her.
I can't really comment right now as the cats need to be broken in (Need to fill up with carbon to reduce drone and resonance) but right now they are pretty loud when the car is under load. Drone is minimal but then again I have a Stillen CBE. The sound now sounds identical to a 03-07 G35 coupe with an intake + exhaust. It's really amazing! So far i love it and it should be even better after i get more miles on the odometer.