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uppipe and ewg

6.7K views 10 replies 5 participants last post by  man show  
#1 ·
so, for a 2011 wrx wagon, would a 44 mm uppipe and ewg be better for a stock turbo? or the 38mm uppipe and ewg be better? im trying to figure out the best combination to go with a catless downpipe.
 
#7 ·
Yup, my GS 3 port ebcs did the trick.

FWIW, the 44 would probably also work, but it would sound a little deeper. It's overkill for a stock turbo though since it was really designed to regulate ginormous aftermarket turbos.

Make a list of questions and talk to your tuner !Thumbs Up
 
#8 ·
Actually if I remember reading somewhere big ewgs are good for small turbos and small ewgs are good for big turbos. I'm sure if you google you'll find some egg heads theory on it. Just a thought
 
#9 ·
Regarding 38 mm vs. 44 mm ewgs (taken from Unabomber's Manifesto):

"That is a question for your turbo vendor and tuner as sometimes their advice counters the external wastegate sizing theory. The theory is that a larger wastegate (44 mm) should be utilized on turbos using low boost vs. turbos that are running high boost which should run a smaller wastegate (38 mm). Where did this theory come from? Remember…a wastegate limits boost. If you want to run more boost, you don’t have to limit it as much. Running less boost means you have to limit it more. Think this premise through to get a good mental picture of it as this concept is terribly misunderstood."

I was wrong - boost seems to be the real variable in determining which size is correct, not necessarily turbo size. But I guess when you have a small turbo, you're more likely to want to max it out and use high boost, so you'll want a smaller ewg. With a larger turbo (unless you've really done your homework and eliminated all limiting factors), you probably won't need to run as much boost and you'll still make plenty of power, so the larger one would be better suited for that application. So I guess I was partially right after all.

Anyway, the bottom line is: talk to your tuner :)
 
#10 ·
Hmmmm but what's a lot of boost!? A stock turbo runs 23-24 psi but only in the mid range (15-16 at redline where boost is hardest to hold and most important) while other turbos run to 30-40-50psi. Where's the cut off in this theory?

Anywho it doesn't matter. Both have been done on every application. You get 5-10 more hp if that. so really plus the tune you pay $500-900 for just a little power.
 
#11 ·
Yeah, I was wondering the same thing - what's the cutoff between "low" boost and "high" boost? When it comes down to it, it's a 6 mm difference in piping, which I guess can flow a significantly different volume of air if you know about that kind of stuff.

My 38 mm ewg seems to be most active between 18-22 psi... or at least that's when I can clearly hear it blasting like an angry honey badger :D