Are most catalytic converters directional? - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

yukon · 07-07-2010, 12:56 AM

I bought a bosal for my 240sx with no arrow so I assumed direction did not matter. have had low back pressure and high nitrogen emissions since i installed new cat. othe emission gasses are doing ok.

projectRDM · 07-07-2010, 02:57 PM

Random Technology cats are directional for certain, though I don't know about other suppliers I'd say it's a good bet the Bosal unit is too.

slider2828 · 07-07-2010, 03:16 PM

I know catco's are directional..

Pacman · 07-07-2010, 11:14 PM

Good thing to keep in mind when they can be installed either way: put the catalyst substrate closets to the engine. If you remove it, you may notice the substrat is closer to one flange than the other. Put that side on engine side.

07-07-2010, 12:56 AM	#1
yukon Zilvia Member Join Date: May 2009 Location: boston Age: 35 Posts: 157 Trader Rating: (0) Feedback Score: 0 reviews	Are most catalytic converters directional? I bought a bosal for my 240sx with no arrow so I assumed direction did not matter. have had low back pressure and high nitrogen emissions since i installed new cat. othe emission gasses are doing ok.

07-07-2010, 02:57 PM	#2
projectRDM Post Whore! Join Date: Dec 2002 Location: Atlanta Age: 51 Posts: 13,812 Trader Rating: (12) Feedback Score: 12 reviews	Random Technology cats are directional for certain, though I don't know about other suppliers I'd say it's a good bet the Bosal unit is too. __________________ FORMERLY R240NA Learn what's really going on and protect your assets now before they're gone forever: www.paypalsucks.com

07-07-2010, 03:16 PM	#3
slider2828 Post Whore! Join Date: Oct 2004 Location: San Francisco, CA Posts: 6,040 Trader Rating: (13) Feedback Score: 13 reviews	I know catco's are directional.. __________________ Turn and Burn!

07-07-2010, 11:14 PM	#4
Pacman Zilvia FREAK! Join Date: Sep 2003 Location: Ohio Age: 37 Posts: 1,149 Trader Rating: (1) Feedback Score: 1 reviews	Good thing to keep in mind when they can be installed either way: put the catalyst substrate closets to the engine. If you remove it, you may notice the substrat is closer to one flange than the other. Put that side on engine side.