club.liberty.asn.au

Hey Guys

i got an opportunity to buy a replacement stock exhaust system from a N/A 2.5 liberty..

Is this just a straight swap or is there size differences between the 2..

Thanks

Adam

Why do you want to buy a stock exhaust?

ESP an N/A exhaust when presumably your driving a turbo

you're gonna have to cut the center pipe as well as the NA pipe is longer than the ones from the GT.

swingn wrote:Why do you want to buy a stock exhaust?

its not for me its for a friend who just bought a liberty N/A that has a upgraded exhaust system (i dont know which one yet, havent seen it)

and as he bought it for his wife he needs it 100% quiet, so he wants to source a stock exhaust system and will give me his current one for cheap on the condition i provide him with a stock one..

I dont want to give him mine cause i wanna swap it back to stock once i finished my lease..

overl0ad wrote:you're gonna have to cut the center pipe as well as the NA pipe is longer than the ones from the GT.

so it will need some modification..

i already have the Phat dump pipe, so i can utilize the mufflers from the N/A and just purchase a center piece right? or is it more complicated then that

gtspec wrote:

overl0ad wrote:you're gonna have to cut the center pipe as well as the NA pipe is longer than the ones from the GT.

so it will need some modification..

i already have the Phat dump pipe, so i can utilize the mufflers from the N/A and just purchase a center piece right? or is it more complicated then that

What size mufflers and pipe is the aftermarket n/a exhaust?

If the pipe and mufflers are big enough (2.5" or 3") then you can easily fit (minor cuts and welds) it to your car with the dump pipe.

Are the mufflers straight thru? n/a cars need a bit of backpressure in the exhaust while turbo cars should have no back pressure at all - you might want to consider this as well.

Just to clarify backpressure vs efficiency, as backpressure stories are all over the place! (Sorry for taking another thread a bit off topic...)

My belief is that NA cars don't need backpressure for low-down torque. You need pipework that is optimised to give high air speeds (and therefore peak efficiency/cylinder scavenging) at low-mid rpm ranges. As a byproduct, this will cause backpressure at higher rpm because the pipework becomes a restriction. The only other reason that backpressure might have an apparent performance benefit is if the car has been specifically tuned for a particularly restrictive exhaust, and by changing it you are, in effect, taking it out of tune - or if you put a ridiculously large exhaust on your car, and you kill the air speed in the exhaust system.

So yes, technically speaking, you often need something that is likely to be a restriction at high rpm if you want to maximise your low rpm torque, but it's not because the engine needs resistance, it's because the smaller diameter piping will give higher air speeds at low rpm than larger diameter, freer-flowing pipework.

Basically, you want the smallest diameter exhaust that delivers as close as possible to zero backpressure at the engine's maximum possible air volume.

/off topic blabbing

subnub wrote:Just to clarify backpressure vs efficiency, as backpressure stories are all over the place! (Sorry for taking another thread a bit off topic...)

My belief is that NA cars don't need backpressure for low-down torque. You need pipework that is optimised to give high air speeds (and therefore peak efficiency/cylinder scavenging) at low-mid rpm ranges. As a byproduct, this will cause backpressure at higher rpm because the pipework becomes a restriction. The only other reason that backpressure might have an apparent performance benefit is if the car has been specifically tuned for a particularly restrictive exhaust, and by changing it you are, in effect, taking it out of tune - or if you put a ridiculously large exhaust on your car, and you kill the air speed in the exhaust system.

So yes, technically speaking, you often need something that is likely to be a restriction at high rpm if you want to maximise your low rpm torque, but it's not because the engine needs resistance, it's because the smaller diameter piping will give higher air speeds at low rpm than larger diameter, freer-flowing pipework.

Basically, you want the smallest diameter exhaust that delivers as close as possible to zero backpressure at the engine's maximum possible air volume.

/off topic blabbing

ok

Mo_GT wrote:

gtspec wrote:

overl0ad wrote:you're gonna have to cut the center pipe as well as the NA pipe is longer than the ones from the GT.

so it will need some modification..

i already have the Phat dump pipe, so i can utilize the mufflers from the N/A and just purchase a center piece right? or is it more complicated then that

What size mufflers and pipe is the aftermarket n/a exhaust?

If the pipe and mufflers are big enough (2.5" or 3") then you can easily fit (minor cuts and welds) it to your car with the dump pipe.

Are the mufflers straight thru? n/a cars need a bit of backpressure in the exhaust while turbo cars should have no back pressure at all - you might want to consider this as well.

im not sure about the muffler and pipe sizes.. i have yet to see the parts as im in for a bit of a drive.. but wanted to see if anyone knew off the top of there head if it would work, without any major downsides of course...

i will try find out all the size details