How good is a CAT back exhaust?

[chaddicus]

I found this cat back for really cheap and want to know how good it is.

[masticatingcow]

At least tell us how big this catback is. Crush bent or mandrel bend?

[chaddicus]

3" stainless steel T.I.G Welded N1 style with Silencer. Manderel Bend.

[1991S13]

Are you using it with a NA setup or turbo? For NA 3" is a little bit big (my opinion) but it sounds good. I would go with a high flow (or gutted if you're not worried about emissions) converter too, the stock converter is too restrictive and would take away from gains you would get from the exhaust.

[chaddicus]

Ok I assume my car is just a NA, it's stock. Anyways, what about the converter? I'm car stupid so help me out. This Catback is just the tailpipe and the muffler from what I gather. Do I need to change my converter as well?

[1991S13]

NA (Naturally Aspirated) means the engine is non-turbo.

Catback exhaust is everything behind the catalytic converter.

The catalytic converter bolts in between the header and midpipe. It's an emissions control device, so it is needed for the car to pass inspection/emissions. The stock catalytic converter is restrictive, so a catback exhaust will work better with a high flow converter since the high flow won't restrict exhaust flow. It is not a necessity to replace the stock catalytic converter, but to take full advantage of your exhaust system you should go with high flow. Catco and Magnaflow are two companies I know of that make them. Be careful when picking one so you don't get something that will cause headaches in the future.

[ArcherV20]

I can't help but think that he's still a little confused.

Cliff notes of what 1991S13 said:

- For an Non-turbo engine 3'' is a little big- Catback means from the catalytic conv back.- Stock cat is restrictive- It is not necessary but reccomended to get a high flowing cat to maximize the exhaust systems efficiency.

[ward]

for a n/a 240 3" is a bit large and you will not have the low-end tork of your engine. i would go for a 2 1/2" - 2 1/4" - 60mm i believe that would work best

[chaddicus]

where's a good website to find a 2 1/4 or 2 1/2 at?

[1991S13]

I think pretty much any local auto parts store can get you that size pipe (I got mine at a place in town - 7ft. for around $20 I believe.)

Then take the exhaust off your car to a shop that has a pipe bender, and tell them to bend the new pipe like the old. Mine was straight from the converter to the big bend where it goes under the rear, eliminated a lot of little bends. You'll have to put in a few little bends here and there to make it fit right, but its not that complicated.

Or if you just give the pipe and a muffler to a shop that is gonna put it on they will take care of it, lol.

[chaddicus]

Ok, well I'm looking at these catback exhaust on ebay. How good is the quality? IF you could just do the basic 240sx exhaust on ebay and tell me what you think. I'm not looking at the single mufflers going for 50 bucks. I'm looking at the mufflers with the piping included. the ones around like 280ish. Tell me what you think. Sense apparently I spend too much time on ebay according to some people on here, I thought I'd get a second or more opinion. Thanks

[masticatingcow]

The only thing I ever got for my car off eBay was my OEM shift knob. I wouldn't trust eBay quality all the time, unless you are buying BRAND NEW from an authorized distributor. Almost everything I've ever got for my car has been a hook up, 99% of the time through NICO. Only quality stuff here.

Just recently I got an authentic Apex N1 Dual Catback for less than half off MSRP from a friend. No knock off "Apex-style" crap here. So just keep your eyes peeled, and pay special attention to the B/S/T forums. Most of the stuff on there is for some incarnation of the 240sx, so you won't have trouble getting it hooked up in fairly short order.

Use eBay as a last resort.

[Nismo_Freak]

for a n/a 240 3" is a bit large and you will not have the low-end tork of your engine. i would go for a 2 1/2" - 2 1/4" - 60mm i believe that would work best

3" makes more power, and you are talking about a 2-3 lb. ft. difference in torque at low RPM.

Don't believe me then research exhaust modifications on KA's.

[mattsherr2]

3" makes more power, and you are talking about a 2-3 lb. ft. difference in torque at low RPM.

Don't believe me then research exhaust modifications on KA's.

So, is the general concensus that although the stock 240sx has less than 3" piping, it is OK to replace from the catback WITH 3" ... My friend said he suggested 2.5" or 2.25" because he fears a loss of back pressure to the dual overhead portion of the engine.

BUT, I think you all are the experts here (i know you are), so, can I just get a definitive YES or NO so I can buy what I need to buy?

3" OK? YES / NO ........?

Thanks, Matt

3" makes more power, and you are talking about a 2-3 lb. ft. difference in torque at low RPM.

Don't believe me then research exhaust modifications on KA's.

[masticatingcow]

Yes. It's been proven, no matter what people say.

[jchilders04]

speaking of which.... zerothread?id=48608 !