how much does having/not having a silencer effect performance?

[ANVIL]

i know i should have a certain amount of back pressure in my exhaust system, but right now i am running 3" turboback to an N1 style muffler without the silencer. does not having it help or hurt me or not do anything but effect the sound? i dont know if its in my head or not but it seems like i backfire a lot more without it

[Adrian gt]

you're turbo makes moe than enough back pressure anything after the turbo to reduce pressure will help your hp. only thing it might hurt a little and i;ve seen this on subarus with headers is it might hurt torque just a tad before you'e in boost

[Cpt_Impossible]

i know i should have a certain amount of back pressure in my exhaust system, but right now i am running 3" turboback to an N1 style muffler without the silencer. does not having it help or hurt me or not do anything but effect the sound? i dont know if its in my head or not but it seems like i backfire a lot more without it

What??? No No No. On a turbo car you want as little back pressure as you can legally or ethically get. A silencer not only makes your car sound like crap, it limits the exhaust flow and therefore your turbo's ability to make power. My friends DSM would hit 21psi without a silencer and only like 17 with it in. Unless you just need to keep a low profile around the local 5-0, run as big of an exhaust as you can. Personally I have 3" downpipe, 3" test pipe, 3" N1.

[Darius]

What cpt_impossible said.

[FriedEGs]

Good old backpressure.. lol.. The turbo is fighting to spin faster but the air can't escape fast enough... so it slows down and moans.. and cries..

[nismopwr240]

Good old backpressure.. lol.. The turbo is fighting to spin faster but the air can't escape fast enough... so it slows down and moans.. and cries..

yeah what a little *****

[Abdo]

yeah what a little *****

lmfao....

What cpt_impossible said.

[DriftX]

just stab a 3in exhaust and be done with it.

[Cjmartz2k]

OK, I don't know how many car sites I'm going to have to type this on, but here it goes again:

Back pressure of any kind is ALWAYS BAD. What people think they are talking about is exhaust gas velocity (EGV). Smaller piping for the same amount of flow means higher EGV which helps exhaust gas scavenging in the cylinder there by increasing hp (think putting your finger over the end of a hose). Having giant piping with a kink to "give you some back pressure" is about the worst combo of things you could do to you exhaust.

What you want is the smallest exhaust with the smoothest and least bends that won't restrict you at the top end of you RPM range.

That being said, all of the above is for N/A cars.

Now for Turbo cars:

All of the aforementioned EGV, exhaust gast scavenging, etc is negated by the fact that you have one big *** restriction in you exhaust; i.e. your turbo. It completely ****s up the flow of the exhaust, and adds some restriction to boot. On the plus side, the 5-10hp you loose because of that restriction adds from 50-1000hp depending on the size of your turbine.

So, in summary;

N/A (or supercharged)=you can go too big with the piping. Keep them smooth, straight and moderately sized.

Turbo= As least restricted (read big or smooth/straight) as you can after the turbo.

I hope most of that made sense, because I'm having to squint with one I to find the keys I'm so drunk right now.

[Darius]

Clear. Concise. And from a drunk guy nonetheless!! Nice summary!

[FriedEGs]

that ssummary souunds spot on!!

i'm drunk two....