where to tap external WG?

[92eagleTSI]

When i got my talon i noticed the tial external gate is tapped off of the #4 runner. Now i was wondering if it matters which runner you come off of because i've noticed most people say the #1 runner? IMO i can't see why it would make a difference but maybe i'm wrong.

 

[NewB2dsm]

So let me get this straight. When you open the hood the tial is of the "left" of the turbo towards the air intake side? As in as far away as the timing belt as possible?

 

[92eagleTSI]

Yes you would be correct sir.. although i've had problems with everything else the wastegate isn't one. I mean it opens right up at full boost with no creep so figured its not an issue. Is there something i'm missing?

 

[92eagleTSI]

Good answer

 

[Staytuned]

Performance wise it should not make any difference at all which side it is on....plumbing wise it is the opposite side of the O2 housing which makes routing it back to the down pipe "a little tricky".

 

[DSM90AWD]

You would ultimately want the wastegate plumbed in the collector of the manifold to bypass exhaust equally from all four cylinders as plumbing off a single one would cause that cyl to run slightly leaner (less exhaust backpressure). This is why many shops recommend the O2 mount as it bypasses equally.

In a manifold mount, I would think since #1 is the leanest cyl to begin (ok maybe #2 ) with, #4 would be a better choice for the WG. Then again Buschur/RRE have been mounting WGs off the #1 runner for over a decade

 

[92eagleTSI]

I agree that the collector would be ideal or where all 4 runners are together. How would tapping off of a single runner cause that cyl to run leaner? I'm not doubting you i'm just not sure that i understand how that works. And my gate is open, i ran my pipe down underneath the motor and everything is wrapped in headerwrap which helped alot with keeping temps down under the hood. The kid that hacked and rigged this car up previously used gas piping like the stuff that natural gas runs through your house in, i'm sure flow was affected a little aside from looking #### stupid. After 1.5 years i'm finally getting everything straight. Thanks for your help and for bumpin it. Impatient

 

[DSM90AWD]

How would tapping off of a single runner cause that cyl to run leaner?

A turbine spins by the pressure differential btw the manifold and downpipe. Depending on how efficient your turbine housing/wheel is you will have varying amounts of backpressure in the manaifold. This backpressure restricts the amount of exhaust that flows out of the Cylinders on the exhaust stroke which causes some degree of dilution in the mixture.

"Theory" is that placing a wastegate off just one runner will increase the VE of just that one cylinder and cause it to run leaner than the other three.

In practice, it is just not easy to plumb a WG to the collector on a cast manifold so running off the #1 runner (near the collector) has been the norm

 

[92eagleTSI]

thanks for the help guys I wasn't sure myself so i called on my fellow tuners. i have one more question though does anyone know the percentage of power loss through an AWD AUTO? Once again thanks guys.

 

[blcknspo0ln]

thanks for the help guys I wasn't sure myself so i called on my fellow tuners. i have one more question though does anyone know the percentage of power loss through an AWD AUTO? Once again thanks guys.

since DSM90AWD answered your first question, I'll answer your last. It is guessed to be right around the 25% power train loss. Of course there is no real way to tell unless you get your horsepower dynoed at the crank and then at the wheels, but that would not make any sense. If you are concerned about your WHP vs. CHP, juts make more power

 

[92eagleTSI]

more is better. I just wanted an idea it's gonna get dynoed probably at Buschur at shootouts this year just didn't wanna be too disappointed. Thanks