Hey guys,

i have a 2005 AM DB9. I was thinking of getting the quicksilver SuperSport exhaust. I was told the combination of the Sport one plus the secondary catalysts will provide an even more aggressive/louder/refined sound. I was wondering if anyone can give input on that, and also are the secondary catalysts legal in California? Will they pass smog?

Here is the link:
http://www.quicksilverexhausts.com/A...ctbulletin.htm

Thanks in advance!

 

Legal in california?...no

Will it pass smog?...only if your smog station has no idea what a stock cat looks like which is highly likely...the O2 sensors will still be there so there won't be a code, so you'll pass.

You might want to look into Velocity AP as they have headers also with primary cat elimination and O2 sensor wiring extensions for relocating in front of secondary cats...and a new tune to match...nice kit!

They've also just launched an X-Pipe version of their exhausts...this will set your DB9 apart from the rest!

 

Ca cats need to pass a physical inspection, i.e., they must see a stamp that is unique for Ca. even if cats pass all other tests, no stamp no pass.

 

Assuming that they look at the cats which they have never done in all my years of smog tests...and secondary cats are so easy to remove and replace it would be worth it every couple of years if you wanted to be better safe than sorry at smog test time.

 

Not sure how it is in NorCal, but apparently in SoCal the smog check stations can only charge you if your car passes the test (from what I'm told). That being, there are plenty of "indie" shops that will be glad to pass you regardless of what you have bolted on underneath.

 

i read from an unreliable source that high flow cats, while being illegal will still pass emissions, whereas straight pipes/race pipes/cat delete's will not. Is this true? If yes, aren't these secondary catalyst replacements from QS straight pipes causing the emissions test/smog check to fail?

 

Said... Cats are not straight pipes...they are still catalysts and have O2 sensors, and don't forget you still have primary catalysts up front on the manifolds as well. You will pass on the emissions without issue.

Cats come in different cell counts and the recommended road going aftemarket secondaries are 200 cell...especially with coming requirements in CA.

No matter what...a shop "friendly" to exotics will pass you on smog...and your corner smog station will likely not have a clue what to look for and have no real motivation to look as their profits on smog tests are small...it's about churning out the volume to make a buck.

Get the X-pipe from Velocity...QS won't sound nearly as good! Then get the Cats later if you want an even racier sound and a little more HP.

 

Thanks for the clarification @Wildbob, my knowledge about these things is very limited, appreciate your input. My parts are already in transit. I only heard good things about the QS though. Will post a video of the sound shortly.