Exhausts

[axewielder]

Back pressure is caused by using too large a diameter! So fitting a larger exhaust causes the gasses to slow down, THAT is what causes back pressure!

i was pretty sure smaller bore=more back pressure as it restricts flow and therefore helps stop the engine blowing fresh charge straight out the exhaust port on the overlap
big bore=less back pressure which is good for turbos ect as it is less restriction and increased flow + gas speed to help turbo spooling
if its just cat back system there will still be the origional bore on the first part of the system so wont do anything drasticly massive to the engine performance either way

[Adam]

A NA engine relays on back pressure 

[Wayne]

Back pressure is caused by using too large a diameter! So fitting a larger exhaust causes the gasses to slow down, THAT is what causes back pressure!

i was pretty sure smaller bore=more back pressure as it restricts flow and therefore helps stop the engine blowing fresh charge straight out the exhaust port on the overlap
big bore=less back pressure which is good for turbos ect as it is less restriction and increased flow + gas speed to help turbo spooling
if its just cat back system there will still be the origional bore on the first part of the system so wont do anything drasticly massive to the engine performance either way

I am thinking the same.

[VR6-Joe]

Thanks for the replies, I see some of you are concerned about the damage that my happen to my engine

The exhaust is a stainless steel cat back system off a 16v

So far from this thread I've established the 16v/VR6 exhaust is 2.25" (thanks Mike) .. my 1.6 is a 1996 if that makes any difference to the size of my exhaust? I would measure it but it's on the car and I'll be needing the car to go to a tyre/exhaust place to buy a reducer lol.

[Mikester]

You can measure it on the car ok.

I know that a 1.8 GL like shadys uses the same as a 8v gti bore, which is 2inch.

But im not sure about yours, i would look on a parts website and see if the exhaust parts are listed the same for a 1.6 and 1.8. That way you will know if it will fit.

[axewielder]

no damage, just noise+shift the power band up a bit, might reduce overall power by 0.1hp too if ure lucky 

[justalex81]

i'm gonna put a ferrari exhaust on mine. should add at least 300bhp to my abf 

[Cable]

Nah they add 400bhp 

[justalex81]

oh in that case i'm gonna stick bugatti veyron wing mirrors on it. should be good for 9000 torques 

[Cable]

haha, yh 0.90000 torques