Adding cats to Off-Road H-pipe?

Bad89stang · 02-01-2002, 02:50 AM

Can it be done? Do they just cut away a section and weld in the cats? I have off-road exhaust and am thinking about having them added. I also have no smog pump. Will that foul up the cats and ruin them? I heard that certain contaminants can shorten the life of the cats. How much, if any HP will I lose if I use a good flowing cat? 1989 LX. Any help would be great.

NO, I am not tired of the loud exhaust. I love it. Tired of hassling with emmisions and convincing guys to pass the thing. Eventually I may run out of connections.

Skyman · 02-01-2002, 02:55 AM

Yeah I dont see why you can't do that. I was going to do just like you said.

I am not sure on the smog pump, but I am pretty sure it needs to be hooked up for the cats.

Skyler

Smokedawg · 02-01-2002, 06:57 AM

If shipping wouldnt be to much, I would just send you my stock H-Pipe. But I can imagine a pretty good size shipping bill for the whole H-pipe..

Rebel79 · 02-01-2002, 10:58 AM

Why not just buy a High Flow H-pipe with 2 cats? I think it would be a lot easier than cutting up an off-road pipe!

jimberg · 02-01-2002, 11:10 AM

I agree with Rebel79. The pipes on an off-road may be bent differently since they don't need to make room for the cats.

Oh, and yes, you must have the air pump hooked up for cats to work properly. The catalysts need oxygen to work. If they aren't working properly they will get clogged.

Rebel79 · 02-01-2002, 02:14 PM

Quote:

Originally posted by jimberg
Oh, and yes, you must have the air pump hooked up for cats to work properly. The catalysts need oxygen to work. If they aren't working properly they will get clogged.

Yeah I forgot to add that. But if you want a fail safe way to pass smog, get an air stream thats ALWAYS on going to the cats. The Smog pump does not give air to the cats at idle, so they are not 'working'.

02-01-2002, 02:50 AM	#1
Bad89stang Registered Member Join Date: Aug 2001 Location: Ft. Worth, TX Posts: 456	Adding cats to Off-Road H-pipe? Can it be done? Do they just cut away a section and weld in the cats? I have off-road exhaust and am thinking about having them added. I also have no smog pump. Will that foul up the cats and ruin them? I heard that certain contaminants can shorten the life of the cats. How much, if any HP will I lose if I use a good flowing cat? 1989 LX. Any help would be great. NO, I am not tired of the loud exhaust. I love it. Tired of hassling with emmisions and convincing guys to pass the thing. Eventually I may run out of connections. __________________ You're gonna need your seatbelt

02-01-2002, 02:55 AM	#2
Skyman I need 110mph Trap Speed! Join Date: Feb 1999 Location: So, CA Posts: 4,315	Yeah I dont see why you can't do that. I was going to do just like you said. I am not sure on the smog pump, but I am pretty sure it needs to be hooked up for the cats. Skyler __________________ 2001 BMW M3 6spd 12.79@108 RIP ---- 1993 Notch w/ 98 4V 4.6 Fasttt... -1989 Saleen Mustang #406- 12.32@109 -1999 Black Cobra Coupe- JBA Shorties, Bassani Cat-X, Magnaflow 3", Pulleys, 85mm Pro-M, Ported Intake, Soild Rear w/ 4.30s, Tubular Front End, X2C arms, 13lb batt, few others.

02-01-2002, 06:57 AM	#3
Smokedawg Tires Fear Me... Join Date: Jan 2001 Posts: 867	If shipping wouldnt be to much, I would just send you my stock H-Pipe. But I can imagine a pretty good size shipping bill for the whole H-pipe.. __________________ 1990 Mustang GT- 347 Stroker-Tremec 3550-Compucar Nitrous, AFR, Systemax Intake, AFM, 30lbers, 70MM TB, 76mm MAF, full suspension and lots more 1995 Chevy S-10 406 SBC, Dual tunnel ram, Dart heads, Nitrous, full tub, 4-link, adjustable drag shocks, coil-overs, 9in rearend, 4.56 gears...etc

02-01-2002, 10:58 AM	#4
Rebel79 News Editor Join Date: Apr 1999 Location: Concord, CA Posts: 2,101	Why not just buy a High Flow H-pipe with 2 cats? I think it would be a lot easier than cutting up an off-road pipe! __________________ Scott Halihan, News Editor The MustangWorks Magazine 1994 Supercharged Mustang Cobra Rebel Racing. Home of Bay Area Mustangs

02-01-2002, 11:10 AM	#5
jimberg Registered Member Join Date: Oct 1998 Location: Rogers, MN Posts: 2,089	I agree with Rebel79. The pipes on an off-road may be bent differently since they don't need to make room for the cats. Oh, and yes, you must have the air pump hooked up for cats to work properly. The catalysts need oxygen to work. If they aren't working properly they will get clogged. __________________ 351W 89 Mustang GT Convertible

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