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piping

Posted: Mon Jul 20, 2009 6:49 pm
by redevil3883
hello guys, what's the best size exhaust piping for a 4speed triptronic fto ?

Posted: Mon Jul 20, 2009 6:53 pm
by Bennoz
2.5 inch

Posted: Mon Jul 20, 2009 6:58 pm
by redevil3883
2.5 inch ?? is that too big ? last time i try it , but feel like no power for the car coz i didn't have any modification the car.

Posted: Mon Jul 20, 2009 7:01 pm
by Bennoz
Well standard its 2.25.

You only get a minor gain by just swapping the piping, you get better power from high flow cats and extractors combined with the bigger piping.

And you'll get more from an exhaust if you have done the intake as well. The engine is just a pump, make it breathe & exhale better, it will go better.

Posted: Mon Jul 20, 2009 7:32 pm
by redevil3883
i currently using a exhaust brand kakimoto , the piping more bigger than my original pipe from down pipe , so i feel the car like no power.

or mayb is that more works if i change the whole piping start from extractor ?

Posted: Tue Jul 21, 2009 10:40 am
by Cassf88
whats an extractor ?

*learning time*

Posted: Tue Jul 21, 2009 12:04 pm
by Fulltiltorgasm
Cassf88 wrote:whats an extractor ?

*learning time*
extractor/headers take the exhaust from the engine block down to the start of your exhaust system

Posted: Tue Jul 21, 2009 1:19 pm
by I8A4RE
Fulltiltorgasm wrote:
Cassf88 wrote:whats an extractor ?

*learning time*
extractor/headers take the exhaust from the engine block down to the start of your exhaust system
Close, but your extractors (aka headers) "ARE" the start of your exhaust sytem. They are pipe looking things that take the exhaust gases from the engine to the exhaust pipe.

Posted: Tue Jul 21, 2009 1:33 pm
by col2560
they are an exhaust manifold. they bolt directly to the engine, usually seperate pipes, one for each cylinder.

Image

Posted: Tue Jul 21, 2009 1:36 pm
by Fulltiltorgasm
I8A4RE wrote:
Fulltiltorgasm wrote:
Cassf88 wrote:whats an extractor ?

*learning time*
extractor/headers take the exhaust from the engine block down to the start of your exhaust system
Close, but your extractors (aka headers) "ARE" the start of your exhaust sytem. They are pipe looking things that take the exhaust gases from the engine to the exhaust pipe.

yeah very true i was just trying to simplify it for the young lass :D

Posted: Tue Jul 21, 2009 1:49 pm
by Cassf88
i love u guys :)

thanks


Edit: how do the fumes know to go down the pipe? im assuming theres like a fan or is does it just pressurise?

Posted: Tue Jul 21, 2009 2:19 pm
by Fulltiltorgasm
Cassf88 wrote:i love you guys :)

thanks


Edit: how do the fumes know to go down the pipe? im assuming theres like a fan or is does it just pressurise?
extremely high combustion = high pressure thus the idea of enlargening the exhaust so more can escape, which means that at high rpms the engine can work harder (not as restricted) :D

Posted: Tue Jul 21, 2009 9:26 pm
by chuster
Fulltiltorgasm wrote:
Cassf88 wrote:i love you guys :)

thanks


Edit: how do the fumes know to go down the pipe? im assuming theres like a fan or is does it just pressurise?
extremely high combustion = high pressure thus the idea of enlargening the exhaust so more can escape, which means that at high rpms the engine can work harder (not as restricted) :D
Excuse me if ive intepreted this wrong but i think Cass is asking why do exhaust gases go down the extractors/headers not the benefits of having aftermarket extractors.

Its coz of a difference in pressure between the exhaust gases in the cylinders and the tip of your exhaust, high pressure gases move to low pressure areas hence get blown out the exhaust.

Posted: Wed Jul 22, 2009 7:57 am
by I8A4RE
chuster wrote:
Fulltiltorgasm wrote:
Cassf88 wrote:i love you guys :)

thanks


Edit: how do the fumes know to go down the pipe? im assuming theres like a fan or is does it just pressurise?
extremely high combustion = high pressure thus the idea of enlargening the exhaust so more can escape, which means that at high rpms the engine can work harder (not as restricted) :D
Excuse me if ive intepreted this wrong but i think Cass is asking why do exhaust gases go down the extractors/headers not the benefits of having aftermarket extractors.

Its coz of a difference in pressure between the exhaust gases in the cylinders and the tip of your exhaust, high pressure gases move to low pressure areas hence get blown out the exhaust.
Half correct, also though you have more gases coming from the engine so it has to go somewhere.

Think of it, as benny says "a engine is like a pump. It sucks air in one end and pushes it out the other. If your exhaust was a plastic bag it would keep filling up till it exploaded, as it has no where to go. However your exhaust is not like that its like a straw, so if you blow on a straw, the air is pushed out the end.

Posted: Wed Jul 22, 2009 10:44 am
by Cassf88
chuster wrote:
Its coz of a difference in pressure between the exhaust gases in the cylinders and the tip of your exhaust, high pressure gases move to low pressure areas hence get blown out the exhaust.
so like osmosis but with fumes?

fulltiltorgasm-- i still understand what u mean, so when ppl say dont get a 3in pipe why is that? i know, its 'overkill' n ive heard that from other places not just this forum, but then why do suppliers sell it?

Posted: Wed Jul 22, 2009 11:02 am
by Bennoz
*Tech talks*

Pipe size is directly relevant to the cubic capacity of the motor (ie 2 litre, 3.5 litre etc) and is also directly relevant to whether or not the engine has forced induction such as a turbo.

On naturally aspirated engines (non turbo) such as the FTO motor, the piping size is much more critical. As the exhaust mixture exits the comubstion chamber (in the head of the engine) it goes into the exhaust header in 'pulses' - ie as the piston forces the exhaust gas out, it comes out in a certain volume at a certain speed. When you have 6 cylinders all pulsing out exhaust gas wads, they need to be merged from the 6 cylinders to 1 exhaust pipe. In the FTO's case, each head has 3 cylinders, so we get 2 banks of 3 cylinders merging together, then we get the 2 banks merging into one.

As the gasses all merge together, it creates almost a gas equilibrium effect or a neutral pressure if you will. That pressure within the system keeps the gas pulse merging at the right speeds. Sorta like a a whole bunch of traffic merging into 1 lane, each car letting the next in.

If you are to put piping on that's too big, then you loose that back pressure & the merging of the gas pulses become gas collisions. Gas collisions of course screw up the whole flow-on effect & effectively cause the motor to struggle to get the gas out right & which causes a power loss at the end of the day.

Hope that helps!

Posted: Wed Jul 22, 2009 11:04 am
by Cassf88
WOW... your so good.

lol

Posted: Wed Jul 22, 2009 1:03 pm
by Fulltiltorgasm
Cassf88 wrote:WOW... your so good.

lol
not the first time ive heard that said lol :D :D

Posted: Wed Jul 22, 2009 1:14 pm
by Cassf88
get your mind out of the gutter

Posted: Wed Jul 22, 2009 1:18 pm
by Bennoz
8O