exhuast question

[Mark Guthrie]

anyone ever run a 3" catback exhuast on a 1g without a muffler?
im going to go get my 3" catback put on just a straight pipe with a 45 at the rear end and out the back, then ill put my 3"dp on anyone done this before, it wont be long term but i need to get the dp on and the cat back needs to be done first probably like a week, think it will be too loud? lol 

[Mike Hewitt]

I'm going to say it'll be decently loud...at Idle it'll probably sound like you got a 1000 ponies under and some kind of engine swap. But as  soon as you start going, it'll be loud.

My exhaust is 3" Turbo back with Magnalfow 3" muffler. No cat, no res in between. Just straight. At WOT its pretty loud it goes from vrooooomm, to waaaaaaap!!

But hey its hella fun! All the buddys say the exhaust sounds wicked so.

[Mark Guthrie]

ya ive been looking on youtube and found an eclipse with a 3" straight pipe it didnt sound to bad, so i guess ill just do it and it its to loud well ill put a muffler on it lol, i might just do a cat back for now and leave that little crumby cat in there till i replace the dp

[Mike Hewitt]

Might as well... You're turbo will love it! When I first got my DP it didnt connect to the test pipe on my car so I had to drive it to the muffler shop like that, Turbo spool was faster, and you could hear it spool up and down at a stand still. Was kind of cool for the 10 min drive.

Oh and I had a vacuum hose for the BOV come off on the way there, so the car ran its crappy little way it does. A guy in a a 92-ish chev has this  on his face. Car sounded like it had a big block v8 with cams! 'Till I started moving

[Mark Guthrie]

lol nice, im running a vented blow of valve right now but my car runs really well like that, im gonna probably get r done today hopefully

[John Hartman]

Mark, it will work but it will be quite loud.  Mine is even very loud WITH a quality Borla muffler.  I have no rear interior tho, so that contributes.

Also, WATCH OUT FOR BOOST CREEP when you first do it, its gonna creep quite badly, so you wont be able to go full throttle much over 5000 rpm unless you have fuel and intercooling to back you up.

[Mark Guthrie]

ya once i do it im just going to turn the boost down till i get my fmic in or im going to just remove the mbc and run stock boost im not sure yet, ill deal with it once i get there

[John Hartman]

what I am saying is that you can't control the boost.  Turning it down doesn't do shit once the revs climb.

[Mark Guthrie]

ahhhh yes after re reading your post i understand what your saying, ive been babying it lately anyways

[Zach Holt]

what I am saying is that you can't control the boost.  Turning it down doesn't do shit once the revs climb.

I have a 14 B full 3inch o2 skip down pipe strate 3inch to my 3in 3 out muffler and evo mani. My boost is set for stock "9Psi" at 4000 RPM it hits 11 psi by 6000 its at 16/17 psi. not fun.

Becarful or you will cook your car. 

[Mark Guthrie]

16/17 psi? lol i was hitting 20 for like a month, and i have been babying it cuz i need to put that new valve cover on and change the plugs!

[John Hartman]

20 is way too high.  Absolutely no way your car has the fuel for that kind of airflow.  Plus the 14b is working really hard at that pressure and making the air REALLY hot, so without a fmic, thats no good.

Complete recipe for disaster.

Even with a fmic, 750s, water injection, custom chip, 2g maf, cold air work and some other relevant things, I would see knock occasionally at 20 psi.

[Mark Guthrie]

lol ya i know 20 psi was way to high lol, i was just driving on the highway one day and got into it hard and it took off like a bat outta hell looked at my gauge and it was sitting on 20!! so i eventually found a new boost controller and fixed that issue, now i just need to track down my boost leak, change my valvecover and change the plugs lol, see if that makes things any better