Resonator?

hey guys, im new to this forum.

well I just bought my 96 240sx se, and I love it. but when I bought it I got a discount off it because it had a rattle coming from the resonator.
because I wanted to get new exhaust anyways it didnt really matter.

so my question is, does a resonator matter? will it make it so I dont pass smog? and will it make my car sound like a total rice burner if I just have a after market muffler and no resonator?

I personnaly hate that whole raspy really loud sound of rice burners, but I do want a nice louder then stock exhaust.

so any help would be greatfull.

If you get a cat-back exhaust then you will take out your stock resonator since it's after the cat.

yea, I know that, but I didnt want to do the whole cat back exhaust from those exhaust companies cause there just way to damn expensive and I can get the same thing done for alot cheeper...

im just wondering what kind of difference I will get from not having any sort of resonator?

Sure exhaust systems are pricey and sure you pay for the name on it, but those companies still spend a lot of time and money designing them, some drunk high school drop-out crackhead at the local muffler shop won't give you an exhaust nearly as good as a brand name one.

I seriously dont see how the bigger pipes coming from the cat made by a exhaust company versus bigger pipes made by a exhaust shop will be any different? I mean the only dif will be polished vs not polished....the only reason for them charging so much imo is cause they have to redo all the bends which takes time.

bigger pipes = less resriction to a point, and is the only reason why companies offer cat backs. least thats what I think.

got any reasons why their pipes would be better?

They have to figure out where the pipes go, what kinda of effect the bends will have on back pressure, what angle all the shit is for the exact amout of back pressure, the ground clearance, legal issues like noise and emissions, I'm sure the guy at the muffler shop can make all those careful calculations after he hack-saws your old muffler on and duct tapes a bunch of PVC pipes with an APC neon canister.

geting a custom job at a muffler shop is about half of the cost of one of those cat back systems, just have them use a bigger pipe to make up for the extra bends, you'll get the same gain at about half the cost. =)

You don't need the resonator to pass smog, I recomend taking it off if you are using 2 1/4 inch piping, if you go 2.5 inch it starts getting a little louder. If you want to pay more just have the shop add one on, they make little impact on preformance.

I have 2.5inch with out any resonators or baffles, it's a little on the big side for an NA 240, but it sounds nice and made a big difference on the freeway.

Try 2 1/4 inch pipe with out a resonator, then have them add one in later if it's too loud for ya.

Actually it's been proven that you get bigger gains with a 3" then 2.5" with the N/A KA.

Actually it's been proven that you get bigger gains with a 3" then 2.5" with the N/A KA.

Of course you do, but you lose so much torque after 2 1/4 - 2.5 that it's not worth it at all.

N/A needs that back presure, I'm considering droping mine to 2 1/4 to get some torque back if I ever redo that pipe and I'm still N/A.

EDIT: Also 3" would be loud as hell, my 2.5" sets off many car alarms as it is with all the rumbles and back fires. =P

so will a small glass pack work as a resonator too?

logik, I know what your saying about the smog shops, but the people im going through arnt like that, they are friends of some very good friends of mine and they do alot of performance work...but you could be right, but I would hope not...anyways, yea I was thinking of going 3 inch piping....Ill probably add a resonator if I do 3 inch.

so will a small glass pack work as a resonator too?

logik, I know what your saying about the smog shops, but the people im going through arnt like that, they are friends of some very good friends of mine and they do alot of performance work...but you could be right, but I would hope not...anyways, yea I was thinking of going 3 inch piping....Ill probably add a resonator if I do 3 inch.


Better make it 2 or 3 resonators if you're going with 3" and don't want to set every alarm in the parking lot off. =P

Seriously don't go 3" unless you've got some forced induction lined up, your car will have about as much pickup as a base model ford focus...

I'm just saying my opinion, you can do whatever you like, if you can gte a good exhaust for a low price, then thats great, and Ken, theyre were dyno charts that proved that you get more torque and more horsepower thru the whole powerband with a 3" on a stock KA because its such a big engine.

logik, do u have a link to any of those dyno charts so I can take a lookie?

I'm just saying my opinion, you can do whatever you like, if you can gte a good exhaust for a low price, then thats great, and Ken, theyre were dyno charts that proved that you get more torque and more horsepower thru the whole powerband with a 3" on a stock KA because its such a big engine.

umm, I would like to see those too, I hardly consider 2.4 liters to be big, We've done the exaust on our 72 Trans am 3 times in the last 10 years, went as high as 2.75, then lowered it back down to 2 1/4 after some of the WORST quarter mile times we'd ever seen. Thats engine is over twice the size of the KA ^^

The dyno's your talking about must include some other mods too, you can't get something for nothing, every thing's a trade off.

I don't know where those things are, but everyone is always saying in this forum that you can get more power out of a 3" then a 2.5" and the tradeoff it might not be legal in terms of noise and emissions. But wtv, get a 2.5 if u want, I realy dont care. lol

I don't know where those things are, but everyone is always saying in this forum that you can get more power out of a 3" then a 2.5" and the tradeoff it might not be legal in terms of noise and emissions. But wtv, get a 2.5 if u want, I realy dont care. lol

They are correct, you WILL get more power, but you will also lose LOTS of low end power, you lose so much that it doesn't make up for the gain in HP. go 2.5 MAX, at 2.5 you're losing a considerible amount of torque, and it's going to be quite loud. For what this guys asking, 2.25" with a resonator (after if it's too loud without) and a nice open muffler will give you a nice gain, sacrifice little torque, and will set off only the most sensitive car alarms.

eh, im just wondering you know, dont wanna put 3 inch only to find out its making me lose hp cause its to big.

eh, im just wondering you know, dont wanna put 3 inch only to find out its making me lose hp cause its to big.

You won't lose horse power, you will gain some peak horsepower with a 3" over a 2.5"

You will lose Torque, and LOTS of it, which will make your car accelerate really slowly when the engine is under say 3500rpms, after 3500 your peak horse power will start to pull its weight, just not enough to make up for how long it took you to get up to 3500rpms ^^.

In a quarter mile race, I would bet on the 240 with the 2 1/4" pipe over the one with the 3" pipe, all other factors being the same.

cool, well thanks for your help guys.

Reading older posts... and you said that you would lose LOTS of LOW-END POWER? If Low-End to you is 3500and lower then in the drag you should be fine? I mean you only use LOW-END power in first gear right? in 2nd im at 3250 and in 3rd its at like 4200 and then from there up so you dont use that much LOW-END power? and you talk about the LOSS of torque being so bad that it takes forever to get to through the low end? im guessing your talking like 3-4 seconds?

the lost torque would be most noticable in the 0-3500 rpm range, and it will hurt you on the drag strip more than the extra 1-2 peak HP you gain around 5500 rpms.

On the street you will notice the lost torque much more.

Again, all things being equal, 2.5" vs 3" on the stock 240, I would bet money on the one with 2.5".

First gear is probably the most important gear on the strip anyway ^^

As you increase the diameter you gain less and less horse power, but the loss of torque due to less backpressure remains fairly constant, with that in mind, cars can benefit from making the pipe slightly larger, where the gain in HP out weighs the loss of torque, This is why very few people drive around the street with 12" piping, you don't stand to gain very much horsepower after 3".