3inches DP back for 240 bucks?

[azian6er]

SO, i went to the muffler shop today and I got an estimate for 240 bucks for labor and parts to fab up a 3inch downpipe back exhaust for my baby. Not including the apexi N1 muffler however.

So, Basically I saw the bender he was gonna use and there really wernet that many bends in the piece he uses to bend 3inch pipe. Maybe one small crush every 3inches of pipe or so.

So my question is, If i run no resonator, Just 3inches form downpipe back with just an Apexi N1 turbo muffler, will this set up be loud as s***, or will it be a nice tone? Also, Is going from a 2.5 inch diameter downpipe to a 2.75inch to 3inch cat back section going to be ok with flow issues? I heard somewhere that changing diameters of pipes in the exhaust system is not such a great thing to do. But if i go from smaller to bigger it shouldnt be an issue correct?

Advice appreciated from all.
--Bryan

 

[Equinox]

wont be loud as s***, since the turbo itself muffles exhaust as well as the muffler, but it will be just about as loud as every hond ayou hear, AND it will have somewhat of a ricey reverb, as I like to call it, because of the reliance on that can muffler. You can get away with a can muffler and not have a ricey tone exhaust when you have a cat converter, but when that's gone, out come the rice noise.

Also, changing sizes will only not allow you to have optimum horsepower, but atleast raising the diameter will still give you more horsepower. It's not like you will lose any, you will just not gain as much as possible with a constant diameter.

 

[azian6er]

so would it be better to use 2.5 inch pipe as opposed to 3inch since i am keeping a consatnt diameter?

 

[Equinox]

although there is lots who woudl like to beg to differ, but I suggets yes all the way through 2.5". It should give you the best and optimum results.

 

[azian6er]

The only thing is, if i decide to go all 3inch later in the future, i could make use of the cat back i already have. I dunno, ill probably go with 3inches and see what happens.
--Bryan

 

[DiscreetSpeed]

if your boost is upped or your plannin on it, get the 3".

 

[bored132]

i got 3 in and the n1. Its not 2 loud at all. It sounds so badass.
dont get 2.5 --real turbo cars deserve 3 in.

 

[boostisgood]

DooD, DO NOT GET CRUSH BEND. IT will cause turbulance in the flow of exhaust, thus negating any benefit the larger diameter pipe would give. Why do you think all aftermarket stuff is mandrel bent. you can go on JC Whitneys site, and buy enough 2.5 or 3 inch stainless, mandrel bent pipe for around 200 bucks to do the job. spen the extra 100 150 to have the shop do it, and you got a decent, mandrel bent exhaust.

Yeah its a little more money, but if your gonna do something, do it right or dont do it at all.

 

[Equinox]

3" on the FS series engines is not nessacery, and will show no more gain than 2.5", and will be better especially if you can't go all the way 3" anyhow.

On the bend type, yes you shoudl try and get it mandrel bent, instead of crush bent. Crush bending a pipe shrinks the diameter of the pipe down in a bend, as they have to crush it on the bend. Mandrel bent does not shrink the pipe at the bends. Just call around to muffler shops and ask if they mandrel bend 2.5" pipe. You'll find one in no time.

 

[kwiktsi]

DooD, DO NOT GET CRUSH BEND. IT will cause turbulance in the flow of exhaust, thus negating any benefit the larger diameter pipe would give. Why do you think all aftermarket stuff is mandrel bent. you can go on JC Whitneys site, and buy enough 2.5 or 3 inch stainless, mandrel bent pipe for around 200 bucks to do the job. spen the extra 100 150 to have the shop do it, and you got a decent, mandrel bent exhaust.

Yeah its a little more money, but if your gonna do something, do it right or dont do it at all.

Ahem..... Depends on his goals.. A crush bent 3" will still outflow a mandrel 2.5" and it will outflow the turbo and head on this car no matter what PSI you run.. Unless you plan on running a monster turbo and 25+ psi of boost , I wouldn't sweat it. I was running a press bent on my car and I wasn't worried about it for anything I planned to do to my car.
Joe

 

[azian6er]

Thanks for stickin up for me Joe. I guess good minds think alike

--B

 

[MazdaSpeed0020]

So why is it that everyone says that you should have a 3" piping for the exhaust if it really doesnt make that big of a difference with the lower psi that we are running? I thought that the 3" piping would be the ultimate exhaust because of the big decrease in back pressure?

Matt

 

[igdrasil]

I have a 2.5 DP to back, no resonator, no catalitic, SOUNDS LIKE A TRUCK. Even with backfires and bid detonations, And I mean BIG! Well....that the case of a turboed P5.

I had to install a 2.5 Resonator. The noise was to much.