sushibug

first of all let me explain my setup... greddy turbo, intercooler, bov, running 3psi, custom crush bent 2.25 exhaust all the way back except for the cat and its attached piping pictured below. before, i had a muffler that resembled an over-sized pepsi can... and on the inside it actually went inward a little bit so the muffler has about 2inch of straight flow. i replaced that with a straight through oval-design muffler. its insides are 3inches straight through... the car sounds awesome now... deep and not one bit ricey. but the problem is my car is a lot more slower. i lost a lot of torque and my car takes 500rpm longer to finish spooling up. i dont get it... i though turbos like bigger piping. is it because the cat is so restrictive that i dont benefit from my muffler and i actually lose out?



i took a pic of the muffler but it didnt come out right...


[Modified by sushibug, 7:19 AM 5/8/2002]

2K_TEG

going from 3" back to 2.25" causes more turbulance in the exhaust than just running 2.25" straight back. If you go to 3" go all the way 3", if you want 2.5" go 2.5" all the way. Always go to a bigger diameter piping on the way out, not smaller.

Imagine pouring soda out of a 2 liter, it slows a hell of a lot when it gets to the neck, if the pour spout was the same size as the bottle it would come right out, if the bottle was longer, but a universal diameter (to still hold 2 liters) it would come right out. Hope my rambling didn't just make things worse.

sushibug

does this contradict everything else you wrote? cuz im going from 2.25 to 3... which would agree with the statement i quoted.


[Modified by sushibug, 7:26 AM 5/8/2002]

sushibug

heres some more pics incase they help.





oh and if you guys are wondering why its so oily down there... its cuz i broken an axle and had to replace it


[Modified by sushibug, 7:31 AM 5/8/2002]

SlowB16

WHere did you get that muffler and how much?? I like !!!!

2K_TEG

I though you only changed out a muffler to 3" then went back to 2.25"????

2K_TEG

I cannot tell by these pics what exactly you did. If you are running 2.25" to 3" and 3" all the way out I have no clue what is making your car slower. Maybe you have some restriction in there??? Take it apart and put it back together, make sure everything is sealed up tight (not that it would matter) and make sure there is nothing clogging your pipes (they do not look new). I was under the impression that you ran 2.25" to 3" to 2.25"?? If that is so you need to get rid of the last 2.25."

With all that said, your biggest problem is only running 3 psi, you need to figure that out first.

sushibug

i have 2.25 piping behind the cat to the muffler. the muffler is 3inches wide on the inside. as for where i got the muffler... heh... i found it on the ground at my parents shop.. they let me have it oh.. and i know why i have only 3psi... all i have to do is change a vacuum line to a different spot and i will boost 5. im not doing so because my car is running lean at 4-5psi.

okay.. so the greddy downpipe... 2.25? 2.5? well... it goes to 2", then to 2.25", then to 3". i know its a little screwy but... i used to have a 2" muffler but i lost a lot of power by replacing it with a 3" one.


[Modified by sushibug, 7:52 AM 5/8/2002]

sushibug

oh yeah... the pic with my muffler showing... anyone like my pearl paint job?

2K_TEG

Just try to streamline it...all one piping size. Two at the most. See how that works. K.I.S.S.

93LSivic

Anyone else catch this?? So basically your trying to blow a golf ball through a milkshake straw at looow boost.

I mean, Im still runnin 2.25" cat back, but damn its mandrel bent atleast.

Crush bent 2.25 or more like 1.8"
If your gonna do 3" do it the right way...

sushibug

yeah i know crush bent is bad, but i bought the car and it had that already. the idea of crush bent 3" piping crossed my mind for a very brief second.... im still trying to figure out why my exhaust is making my car crappier. i know velocity is an issue and what not but its turboed...

csufweed

ok, crush bent piping BAD, small diameter crush bent piping is even WORSE! The "turbo" mufflers are restrictive and not straight through. Toss all that for 3" mandrel bent piping and 3" magnaflow or some other straight through muffler like borla or gibson. sheesh... if the muffler is already straight through, then its fine. (you werent too clear)


[Modified by csufweed, 9:40 AM 5/8/2002]

csufweed

just looked at the cat... check to see if it needs replacing and replace it with a 3" one when you get a proper exhaust made.

CovertFI

how was the weather when you took your car out. every time it gets hot out side my under hood temps go up and my car drives like ****, because my intake pipe are hot. at nite my car drives great 70 degres low humidity. during the day 90 degrees like 80% humidity. this always fools me and makes me think some thing is wrong.

B20LS-T

On the upside, I like your paint job It looks like white with blue pearl?

sushibug

yes its white and blue pearl. and it was late at night when i drove... 10pm or so? also, the muffler is 3" straight through on the inside. after a night of sleep im guessing i lost power because im not running enough boost to put 3" to good use..

TheSwift1

that's what i'm thinking...3 lb.s of boost is too less of a backpressure to let the exhaust gas out effieciently...

DIRep972

iTrader: (1)

u need to make it ALL 3" and turn up the boost.. that will solve all your top end/spool up problems.

sushibug

will do.... thing is i just talked to vtc_civic on how much his custom 3" cost... and yikes... that is helluva lot of money.

Xerxes

get a thermal or a used exhaust..i got a used thermal + 3" cat for $350

-Xerxes

FBP Ex-T

i think it was 220 for 2 1/2 in piping for my car 00 civic coupe..but i found GReddy 2 1/2 in and welded it to an Apexi dunk muffler he he thats my setup

MIKES

Don't run straight 3" pipe your car will run slower. Get 2 1/2" piping all the way through and you will be very happy. You have to make over 400 hp to the wheels to ultilize a 3" exhaust. 2 1/2" is all you need.

technine

Whoa, how are you running 3psi? What waste gate and turbo you running? I kinda want to be able to run that low when not running anyone.