axle-back vs cat-back

[Onnipotente]

is there really any difference in performance between an axle-back and cat-back if you were planning to keep the rest of the exhaust stock? since the price difference is a lil over 200 for just the extra piping to the cat, is it really worth it?

5zigen axle-back - $246
5zigen cat-back - $479

 

[leakyfaucet]

since the price difference is a lil over 200 for just the extra piping to the cat, is it really worth it?

Yes. An axle-back system will most likely be a muffler and maybe a little bit more piping.

 

[blcknspo0ln]

axle-backs are offered for people that don't have performance in mind.. just the sound :thumbdown

basically, you're catback is about 5-6 ft. long [ or so ] ... an axle back will free up exhaust flow for the last foot or two... so you're leaving the extra 4-5 feet of STOCK POS 2" piping. i doubt you'll have any gains but if you're all about the sound then just get a muffler with adaptor welded to your stock exhaust. axlebacks are wastes of money IMO.

if you're money tight go to a local muffler shop and have them mandrel/crush bend you a custom exhaust.. itll run you the same amount as the axle back but you'll have a catback.

goodluck, and let us know your goals

 

[Onnipotente]

axle-backs are offered for people that don't have performance in mind.. just the sound :thumbdown

basically, you're catback is about 5-6 ft. long [ or so ] ... an axle back will free up exhaust flow for the last foot or two... so you're leaving the extra 4-5 feet of STOCK POS 2" piping. i doubt you'll have any gains but if you're all about the sound then just get a muffler with adaptor welded to your stock exhaust. axlebacks are wastes of money IMO.

if you're money tight go to a local muffler shop and have them mandrel/crush bend you a custom exhaust.. itll run you the same amount as the axle back but you'll have a catback.

goodluck, and let us know your goals

i figured there would be some gain cauz of the high flowing muffler but i guess the piping is more important than i thought... thanks for the response

 

[leet]

i figured there would be some gain cauz of the high flowing muffler but i guess the piping is more important than i thought... thanks for the response

High flow muffler will only free up the END of your exhaust.

The rest of it is still severely undersized.

 

[saw wave analog]

like the other guy said, if you are going to waste money ona mail order axle back just go to a local shop and have them make you a press bent non stainless catback. it will outperform stock and axleback and still be cheap

 

[14.5 drift]

i figured there would be some gain cauz of the high flowing muffler but i guess the piping is more important than i thought... thanks for the response

Your absolutely right, the stock muffler is extremely restrictive. I simply popped mine off. Sounds like I have an exhaust leak, but still, it was free, not that loud for dd, nice extra punch in mid range and top end, and best of all did i mention it was free? It only takes about 5 minutes o do, just pop it off, drive a few days and if you can't live with it put it back on. There's no way i WOULD SPEND 250 ON AN AXLE BACK THOUGH.

 

[14.5 drift]

also my milage went up about 25 miles per tank. Can't wait to get a full 3 inch 02 eliminator on there

 

[saw wave analog]

god damn! so you are getting what, 45 mpg now? i better go rip my muffler off!

 

[14.5 drift]

god damn! so you are getting what, 45 mpg now? i better go rip my muffler off!

Seriously, thats not what I said at all. Unless youve tried it then don't knock it.


I only did it for fun, first I just dropped the cat, so it was only running a downpipe (very fast, pretty fuggin loud), I thought I would leave it but I noticed no exhaust fumes would be blowing passed my second 02 sensor. No good, put it back on. Then I noticed the muffler had a flange and was easily removed, again took it for a spin to see how it was. Noticably faster with it ff, not nearly as loud as a straight downpipe. So I left it off. I won't be putting a muffler back on til I get a full exhaust with straight through muffler. Again though, the only down fall is that it doesn't sound that good at low rpm's, like a boat almost, kinda gurgly. Good at WOT though.

 

[saw wave analog]

i was kidding man, the way you typed it looked funny.. i think everyone knows what you meant. on topic when i put on my 3" catback i did feel a small high rpm gain, but when i gutted out the stock cat it really opened things up- even on the stock dp. in my experience the cat is easily the most restrictive element in the whole shitty stock system

 

[14.5 drift]

my cat is gutted too helps quite a bit

 

[blcknspo0ln]

Your absolutely right, the stock muffler is extremely restrictive. I simply popped mine off. Sounds like I have an exhaust leak, but still, it was free, not that loud for dd, nice extra punch in mid range and top end, and best of all did i mention it was free? It only takes about 5 minutes o do, just pop it off, drive a few days and if you can't live with it put it back on. There's no way i WOULD SPEND 250 ON AN AXLE BACK THOUGH.

i'm sure you felt that it gave you more HP but i highly doubt you gained any whp from it.. at the most maybe ~1whp...

kinda like removing a resonator or something

 

[14.5 drift]

i'm sure you felt that it gave you more HP but i highly doubt you gained any whp from it.. at the most maybe ~1whp...

kinda like removing a resonator or something

thanks, but no. For every mod I do to my car I road test to see if there is any gains. There's a freeway onramp bt my house that has a long steep incline, and I clock my zero to sixty times.


Remember this is a steep hill

Before removing the muffler, I was clocking consistant 9.5's give or take a tenth, with the muffler off it's consistantly clocking low 9's

so it does help a bit

 

[leakyfaucet]

There's a freeway onramp bt my house that has a long steep incline, and I clock my zero to sixty times.

What do you do? Stop on the onramp?

Seriously, that is a very very unreliable and innacurate way to measure speed.

 

[14.5 drift]

What do you do? Stop on the onramp?

Seriously, that is a very very unreliable and innacurate way to measure speed.

yeah, I do stop on the ramp. I line my front tires on the big arrow painted on the ground, stall it to 3k (I have an automatic) and then I go. I basically fixate on my speedo until it hits 60, and thats how I do it. Also I do my testing at around 2am, ussually about 65 degrees out, same road, same teknique every time. It may not be perfect but it atleast gives some indication, and is pretty consistant.

 

[saw wave analog]

i dont see how its inconsistant if he does it the same way everytime.. i do the same thing with the timer on my cd player actually. when i had a logger my best 0-60 was ~5.2 on a flat rd on stock exhaust, 18psi on t28

 

[BowWow]

Resurrecting this thread for some clarification for a noob.

1. What size is the stock exhaust for the 2g N/T?
a. Downpipe (manifold to catalytic converter)
b. Midpipe (cat to muffler)

2. If the stock pipe is 2.5", why bother with repiping with the cat back stuff? A simple axle back should have the same effect, no?

3. If the stock downpipe is smaller than the 2.5" catback, what's the point of doing a catback? Doesn't it stand to reason that if the constriction is in front of the converter there's no point in doing much after the converter?

4. What kind of performance gains will I get (butt-dyno) with
a. Axleback only
b. Catback only
c. Header, downpipe, stock cat, catback
d. Full 2.5", including header, downpipe, hi-flow cat, catback

Thanks for the more detailed replies!

 

[BowWow]

Apparently nobody knows the answers!

Even if somebody knew the stock exhaust pipe i/d it would be helpful...

 

[braceyoself777]

my cat is gutted too helps quite a bit

I'm trying to stay legit but how much more preformance can you get removing a CAT....it would suck if a COP busted you and your CAT was off.

 

[FatalDreams]

First off: guting the cat on a street car is bad
Second : the performance you would get from doing said mod would get you maybe 2hp and snapier throtle response.
3rd: stock pipeing i beleave is only 2" or 2.25" so if you do a cat back system it would be a big improvment over stock.
4th:how much boost are you going to run? if this is a street car in CA and you do not want to be changing your EM every time its time to smog said car then "I think" the stock EM will work for most applications.
As far as an axle back goes: its kind of a waste of time... spend the cash if you have it for the cat back with mandrel bends. If you don't have that much cash go to the local muffler shop and get a crush bend 3" cat back for turbo 2.5" for n/t, it will flow more than the stock piping.

 

[crimsondragon]

Resurrecting this thread for some clarification for a noob.

1. What size is the stock exhaust for the 2g N/T?
a. Downpipe (manifold to catalytic converter)
b. Midpipe (cat to muffler)

2. If the stock pipe is 2.5", why bother with repiping with the cat back stuff? A simple axle back should have the same effect, no?

3. If the stock downpipe is smaller than the 2.5" catback, what's the point of doing a catback? Doesn't it stand to reason that if the constriction is in front of the converter there's no point in doing much after the converter?

4. What kind of performance gains will I get (butt-dyno) with
a. Axleback only
b. Catback only
c. Header, downpipe, stock cat, catback
d. Full 2.5", including header, downpipe, hi-flow cat, catback

Thanks for the more detailed replies!

1a-b. Pretty sure it's 2.5 inch all the way. Don't quote me on it though. You could always jack the low end up, get on your ass and measure it. It should be the same throughout.
2. If you increase the catback to 3 inch, you'll free up a lot of restriction compared to getting an axleback. It's the difference between running 1 mile and running 2 miles.
3. It would be more pointless to replace a restrictive downpipe before upgrading a catback and/or cat. At least with a catback, once the exhaust air hits that point, it's practically home free out into the atmosphere. With just a downpipe, it won't make much of a difference at all. Imagine a traffic jam. You have a 6 lane highway joining together into a 2 lane. What's the point? You're still stuck. Now imagine a 2 lane highway opening into six lanes. Everyone just guns it from then on.
4a. None. You should get a decibel meter. That's probably the only gains you'll get.
b-d. It ranges from 15 hp to 40hp. Replacing the exhaust doesn't increase much power, it just gets the waste gasses out quicker. Sounds nice too depending on what you get. It's nice to replace it nonetheless because your car will breathe easier and will set you up for bigger things.

 

[dsmsucks]

i dont see how its inconsistant if he does it the same way everytime.. i do the same thing with the timer on my cd player actually. when i had a logger my best 0-60 was ~5.2 on a flat rd on stock exhaust, 18psi on t28

yeah right 0-60 in 5.2 on stock exhaust

BS

 

[hotshot_tsi]

I agree with everyone else, axle backs are for cars in the car show biz or parking lot hero kind of thing. Go full cat back if you have the chance, you could even get a muffler shop to run 3" back for a small amount of funds.

 

[BowWow]

Thanks for the replies! I'll definitely jump under the car and measure the current diameter. My daughter currently has the car 400 miles away, and I was thinking of ordering the parts for when the car returns, but now I'll wait to see what the stock diameter is.

The car is a n/t, so I'll be looking at header, downpipe, hi-flow cat, and cat-back, all in 2.5". 3" may be overkill for a normally aspirated motor, no? I'm also looking for quiet more than not-quiet, but still want the performance. Would tossing a resonator or two in after the cat hamper performance?

Thanks again for the replies!