Is this gonna work??
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Member
Joined: Aug 2008
Posts: 97
Is this gonna work??
Hi, Guys.
I was thinking about to do custom exhaust sys.
3" DP - 3" O.D. x 4' Stainless Steel Tubing - Magnaflow Race Series Muffler
Is this gonna work? Do I need anything else?
I'm gonna buy parts individually and go to the muffler shop
and ask them to put it on together.
I was thinking about to do custom exhaust sys.
3" DP - 3" O.D. x 4' Stainless Steel Tubing - Magnaflow Race Series Muffler
Is this gonna work? Do I need anything else?
I'm gonna buy parts individually and go to the muffler shop
and ask them to put it on together.
Last edited by 00Audi180Q; Sep 3, 2008 at 10:31 AM.
5th Gear
Joined: Sep 2005
Posts: 6,678
From: Colchester, VT
it is my opinion, and not just my opinion, that a 4" on a stock, or close to stock 1.8T motor will not gain you anything but sound, and may actually hurt performance.
You need to think of your exhaust the same as your intake air.
first off, on the intake side, cold air is dense air. good to have.
on the exhaust side though, cold air is still dense air. NOT good to have.
While too small of a pipe will cause back pressure and hurt performance, too large of a pipe doesn't push the exhaust thru the pipe soon enough, and it cools, condenses, and gets harder to push (back pressure).
I'm not just pulling this out of my *** either.
http://www.amazon.com/Induction-Perf...0484922&sr=8-1
you can buy the book yourself and read up on it, and look at the graph outlining pipe sizes vs. Hp.
Personally, 2.5-3" cat back, and no larger. A reduction of a 1/4 to a 1/2 inch from somewhere around the rear axle to the tips would actually help keep exhaust velocity up as its already lost a bunch of heat by that point. Getting that involved in your exhaust setup is bordering useless though w/o a bunch of dyno time to fine tune your pipe for optimum flow/power.
You need to think of your exhaust the same as your intake air.
first off, on the intake side, cold air is dense air. good to have.
on the exhaust side though, cold air is still dense air. NOT good to have.
While too small of a pipe will cause back pressure and hurt performance, too large of a pipe doesn't push the exhaust thru the pipe soon enough, and it cools, condenses, and gets harder to push (back pressure).
I'm not just pulling this out of my *** either.
http://www.amazon.com/Induction-Perf...0484922&sr=8-1
you can buy the book yourself and read up on it, and look at the graph outlining pipe sizes vs. Hp.
Personally, 2.5-3" cat back, and no larger. A reduction of a 1/4 to a 1/2 inch from somewhere around the rear axle to the tips would actually help keep exhaust velocity up as its already lost a bunch of heat by that point. Getting that involved in your exhaust setup is bordering useless though w/o a bunch of dyno time to fine tune your pipe for optimum flow/power.
BTW my exhaust is 3"
1st Gear
Joined: Oct 2007
Posts: 88
From:
it is my opinion, and not just my opinion, that a 4" on a stock, or close to stock 1.8T motor will not gain you anything but sound, and may actually hurt performance.
You need to think of your exhaust the same as your intake air.
first off, on the intake side, cold air is dense air. good to have.
on the exhaust side though, cold air is still dense air. NOT good to have.
While too small of a pipe will cause back pressure and hurt performance, too large of a pipe doesn't push the exhaust thru the pipe soon enough, and it cools, condenses, and gets harder to push (back pressure).
I'm not just pulling this out of my *** either.
http://www.amazon.com/Induction-Perf...0484922&sr=8-1
you can buy the book yourself and read up on it, and look at the graph outlining pipe sizes vs. Hp.
Personally, 2.5-3" cat back, and no larger. A reduction of a 1/4 to a 1/2 inch from somewhere around the rear axle to the tips would actually help keep exhaust velocity up as its already lost a bunch of heat by that point. Getting that involved in your exhaust setup is bordering useless though w/o a bunch of dyno time to fine tune your pipe for optimum flow/power.
You need to think of your exhaust the same as your intake air.
first off, on the intake side, cold air is dense air. good to have.
on the exhaust side though, cold air is still dense air. NOT good to have.
While too small of a pipe will cause back pressure and hurt performance, too large of a pipe doesn't push the exhaust thru the pipe soon enough, and it cools, condenses, and gets harder to push (back pressure).
I'm not just pulling this out of my *** either.
http://www.amazon.com/Induction-Perf...0484922&sr=8-1
you can buy the book yourself and read up on it, and look at the graph outlining pipe sizes vs. Hp.
Personally, 2.5-3" cat back, and no larger. A reduction of a 1/4 to a 1/2 inch from somewhere around the rear axle to the tips would actually help keep exhaust velocity up as its already lost a bunch of heat by that point. Getting that involved in your exhaust setup is bordering useless though w/o a bunch of dyno time to fine tune your pipe for optimum flow/power.
That's fantastic info there friend, but nobody is talking about putting a 4" exhaust on their 1.8t. He said 4' (foot) pipe.
5th Gear
Joined: Sep 2005
Posts: 6,678
From: Colchester, VT
apparently he did. The other hash mark I read as a " turned out to be a piece of dirt on the screen. ha!
Anyway, keep that crap in mind. 4" is too big!
Oh, yeah, you need some backpressure for bottom end, that is correct.
Anyway, keep that crap in mind. 4" is too big!
Oh, yeah, you need some backpressure for bottom end, that is correct.
wow
