Exhaust before turbo?

ASSISTANCE Forced Induction
1

The time is nearing where I can finally boost my car. Right now all I need is the exhaust manifold/downpipe and a few other odds and ends. I plan on going with a 2.5 inch exhaust w/ high flow cat. My question is, Would it be wise to have a custom 2.5 " done before the turbo is installed? This is actually convenient timing as my current muffler has a hole in it. :giggle: I have a real pet peeve for annoying noises as well, so I am also wondering would that 2.5" exhaust make for an annoyingly loud stock ls?

Thanks

MantisX

2

edit
acutally i would say before with the stock header

so u can always go back to stock header and keep the exhuast+ easier to sell down the road

it might be expensver to do it at a later time but i think its worth it

3

If I where you I would wait on an exhaust. Save your money for boost. If your putting an exhaust on a stock ls more than likely it will be annoying. You can take that 200-300 bucks and get and manifold or something. You can always run turbo with open dp and get an exhaust later.

4

Cool. I feel like im kind of throwing money away this close to boost, but Im gonna go ahead and just get the stock muffler replaced.

Thanks for the advice

MantisX

5

stock exhaust is terrible. Get after market 2.5 at least. U might lose 30 whp becuase of it. If ur gonna do a turbo do it right… all of it.

Besides, stock exhaust on a turbo car looks gay. Hit boost and a huge amount of exhaust shoots out of that little tip…

6

Oh no, you misunderstood. I am going 2.5" when I go turbo. The stock is only staying on until I boost. I have a hole in my muffler so I am getting it replaced and keeping the stock exhaust until the turbo is installed. I was gonna go ahead and do 2.5" N/A before turboing but feedback seems to tell me it will be an annoying sound and would probably hurt more than help in the N/A sense.

MantisX

7

just get muffler tape and live with that save money …
than def buy a Dp and manifold run open DP to the exhaust shop (enjoy the turbine spool on your way there) than u will be good.
ps. resinator(longer the cleaner sounding) + “the right muffler” will make for a throatier sounding less raspy exhaust…
I use flowmaster 3" others have used magnaflows…(cheap)
jsut something else to consider for ur custom exhaust setup…

8

umm why are you gona use 2.5" i seen most pplz use 3" if there going turbo

9

from what i understand ive “heard” that 2.5" is plenty for a stock motor being turbo’d w/ low boost…but if you build your motor and are making high power (300-400hp) 3" is needed or will net more performance…hope this doesnt turn this thread into an argument on exhaust sizes just trying to help

10

true 2.5 is good up to 300-400hp but its sound so much better with a 3. When going turbo…I say go all out. the bigger exhaust will help the turbo breath better. Helps it spool faster. If you take that money that your trying to spend on a exhaust and use it towards a mani and dp you wont regret it.

11

Well, my issue with the 3" was that I was worried my car might sit too low and hit alot. My car isnt slammed or anything but its dropped about 1.7" in front and 1.4 in the rear. Will the 3" lead to scraping/hitting problems? I am also on stock 14" wheels, so that doesnt help either.

I am still learning about the turbo world, but my plan was to run low boost while I learn what im doing (Self tuned) then once I learn a bit more, I wanted to forge it out and turn the boost up. My end hp goal is only around 320 or so. I was thinking 2.5" would suffice for that. If 3" will go under a teg smoothly with no clearance issues, I would definitely consider that.

On a side note, I went today and got my muffler replaced for a mere $90. Thing sounds like a hybrid.:hi5: I got a ton of low end and midrange power back too.

Thanks everyone

MantisX

12

you got more power by replacing the muffler???