OPEN DOWN PIPE

M

MILLI_VANILLI

New member

• Nov 17, 2013

• #1

Would running an open down pipe change anything? I know there are some very smart subie owners here i would like to hear what you have to say, cause I am still a boot to the Subie?. thanks

 

Alin

Diehard Car Enthusiast!

• Nov 17, 2013

• #2

Open downpipe screws up with your turbo air flow. I dont know exact details but there definitely are a lot of knowledgeable people here that can tell you exact details. :tup:

 

Spamby

Meat Product Toy

• Nov 17, 2013

• #3

Open downpipe with no muffler or a downpipe with no cat?
Either way, a decrease of back pressure and an overboost scenario could happen. That's what I see happening.
Tune for it if your going to change anything with the downpipe.

 

Alin

Diehard Car Enthusiast!

• Nov 17, 2013

• #4

Spamby said:

Open downpipe with no muffler or a downpipe with no cat?
Either way, a decrease of back pressure and an overboost scenario could happen. That's what I see happening.
Tune for it if your going to change anything with the downpipe.

Click to expand...

I assumed open downpipe meaning the turbo and downpipe only. No other piping afterwards. Kids around here refer to open downpipe as no existing pipe past, say, the front seats. :lol:

 

M

MILLI_VANILLI

New member

• Nov 17, 2013

• #5

THIS car has a GT35 garrtet turbo with a down pipe that extends to about mid drive shaft, then there is a connection for the rest of the exhaust. I took it off to see how it would sound, and though it is loud, it seems to be breathing better. It has already been tuned for cat free exhaust….. I drove it for about an hour and it seems fine……

 

M

MILLI_VANILLI

New member

• Nov 17, 2013

• #6

With a down pipe that long would there be an issue? sorry if i sound like a KID…. but i am learning brother

 

Spamby

Meat Product Toy

• Nov 17, 2013

• #7

Eh, I'm not entirely sure that would hurt anything as essentially it just removing the muffler. However, thinking about pressure and flow and removing piping or the muffler could decrease pressure and increase flow, it may not be a bad idea to keep an eye on things.
Data log to see if things seem normal. These cars seem to be extremely sensitive to even the smallest or mundane changes.
Hell, the gt35 may even like it better.

 

Batmobile_Engage

Squirrel Meat Aficionado.

Staff member

• Nov 18, 2013

• #8

The GT35 most likely will perform better with only the downpipe attached. I would highly recommend getting a tune
specifically for this configuration though. You may not have any problems, but you may have boost spikes, boost creep
or even overboost at low RPM due to the decreased back pressure. If nothing else, contact your tuner and see what
he has to say.

 

Alin

Diehard Car Enthusiast!

• Nov 18, 2013

• #9

Oooooh i have a question!

With the decreased backpressure, would you get the "popping" noise during engine breaking? Or is that only affected by the afr during engine breaking?

 

Batmobile_Engage

Squirrel Meat Aficionado.

Staff member

• Nov 18, 2013

• #10

It's very difficult to say "absolutely yes", because other exhaust components, etc. can have
an effect on this, but I would bet that you will get some pops when you drop it into 3rd and
roll up to a stop light.

 

Alin

Diehard Car Enthusiast!

• Nov 18, 2013

• #11

Batmobile_Engage said:

It's very difficult to say "absolutely yes", because other exhaust components, etc. can have
an effect on this, but I would bet that you will get some pops when you drop it into 3rd and
roll up to a stop light.

Click to expand...

So a lot of things can affect it, maybe even as a combination. Hmmmm. Good to know. Thanks! :tup:

 

M

MILLI_VANILLI

New member

• Nov 18, 2013

• #12

Thanks for the input gentlemen… I drove it all day and the car seems fine. I am defiantly going to keep an eye on things. I plan to data log it as soon as a get a knew dongle for my access port. It really seems to be running better.. Thanks for the knowledge .