Hi-Flow Cat help - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

allmotorKA · 02-02-2002, 10:30 PM

You CAN get 3" diameter inlet/outlet cats from Random instead of the 2-1/2" diameter they list for the 240SX. For the 89-97 240SX, Random lists the 2-1/2" diameter cat as part number as 822530...but according to Random, part number 823030 is a 3" diameter cat which was made for the Maxima, but will work for the 240SX as well.

If the N1 dual has a 3" inlet, I would recommend the 3" Random Tech Cat since the Random Cats have slip type flanges. What I mean is that the mounting flange of the cat is free to slide and rotate on the inlet and outlet pipes of the cat. So if you get the 2-1/2" Random Cat, the outlet pipe may be swallowed by the N1 exhaust making it difficult to seal properly without a steel reinforced exhaust gasket.

02-02-2002, 10:30 PM	#5
allmotorKA Zilvia Member Join Date: Nov 2001 Location: SoCal Posts: 204 Trader Rating: (1) Feedback Score: 1 reviews	You CAN get 3" diameter inlet/outlet cats from Random instead of the 2-1/2" diameter they list for the 240SX. For the 89-97 240SX, Random lists the 2-1/2" diameter cat as part number as 822530...but according to Random, part number 823030 is a 3" diameter cat which was made for the Maxima, but will work for the 240SX as well. If the N1 dual has a 3" inlet, I would recommend the 3" Random Tech Cat since the Random Cats have slip type flanges. What I mean is that the mounting flange of the cat is free to slide and rotate on the inlet and outlet pipes of the cat. So if you get the 2-1/2" Random Cat, the outlet pipe may be swallowed by the N1 exhaust making it difficult to seal properly without a steel reinforced exhaust gasket.