i'm going 2.5in piping but.......

[tonytony]

all the mufflers i've looked at that already have tips either are 2.25" or 3" inlets, i dont want to weld on tips. so i'm thinking maybe i could could Y-pipe the 2.5" single to my 2.25"(maybe it's 2") duel inlets of my brullen. What do you guys think?

[HST]

Why not run 2 2.25" pipes from the headers back. It would flow better.

[gstuning]

2 x "2,25 is stock on Euro 286hp S50,
it´s to big for E30 M20B25 unless your running about 8-11psi boost

[BimmerToad]

Magnaflow makes single 2.5in mufflers. That's what I'm running on my M52.

[tonytony]

the magna flows with the tips alread welded on are the ones i want, but they are only 2.25, so maybe i'll just get a reducer pipe from 2.5 to 2.25. I read somewhere, maybe here that exhaust gases would actuallly flow faster as the pipe narrows, so it wouldn't hurt any and add unnecessary backpressure. but i really love my brullen so maybe Ypipe would be another option..... 2x 2.25 would cost me way too much anyway

[JRKOUPE]

all the mufflers i've looked at that already have tips either are 2.25" or 3" inlets, i dont want to weld on tips. so i'm thinking maybe i could could Y-pipe the 2.5" single to my 2.25"(maybe it's 2") duel inlets of my brullen. What do you guys think?

I did a single 2.5 system including the cat on back, to a 2.5 in/out Borla......I clamped on a tailpipe as I'm not postive what I want long term:






also I am 99% sure Magnaflow has 2.5 in /out.

[asubimmer]

who cares about tips? I like mine better w/out them...less flashy/ricey/FUH RAZE

[tonytony]

I prefer having tips, it adds a nice touch to a car, not everyone is looking for a plain boring sleeper type car. anyway about the magna flows with tips already welded on...... they only have 2.5in inlet, but they do have universal ss mufflers that are 2.5 without tips. I've just decided to reuse my brullen, instead of y-piping in the muffler, it'll just be y-piped before the muffler. I'm thinking of getting a y pipe like this made instead of using the usual y pipe.

[Budget Beater]

magnaflow has full stainless high quality tips as well. Look on magnaflow.com then buy all your magnaflow stuff from www.justmagnaflow.com (cheapest online retailer for magnaflow). hope that helps.

[///M42 sport]

did you decide to go with something like this?

[tonytony]

yeah somethign like that but reverse that and having a single pipe going into a duel inlet

[browntown]

I read somewhere, maybe here that exhaust gases would actuallly flow faster as the pipe narrows,

This is essentially what a venturi pipe does, but venturi's generally have strict entry and outlet cones in fluid dynamics like 30 degrees.
Venturi effect is based on Bernoulli's Principle which states that in fluid flow, an increase in velocity occurs simultaneously with decrease in pressure.

Still sure about your backpressure argument? Unless you have a monster under your hood, do as suggested earlier, and just run 2.25 the whole way.

[tonytony]

well i wasn't trying to argue anything i just wanted to get somethign to work and not hurt as well. tahnks for your insight though