A friend asked me about this yesterday and I had to admit--as painful as it might be--that I have no freakin' clue about this particular subject. He's seen a lot of people post on NASIOC about getting great power gains from going to an EWG even on smaller turbos. In particular, a few individuals were quoting 20+ whp gains on a VF34 with no changes other than EWG. Now, I am aware that EWGs are great for boost control. But what contributes to the supposedly substantial gains on a smaller turbo? I could venture a few guesses (less flow into the downpipe, maybe being able to taper the uppipe more aggressively) but wanted to hear some comments from people who actually know the stuff.
this is why I was considering an EWG. I have also read on NastyHoc that you gain more TQ along with HP..... knowledgeable ppl please chime in!
Can't say that I "know", but as you said (guessed) the flow into the dp would certainly change things around and affect the turbulence that's flowing into the turboback (especially the dp). Also, I'd be real skeptical of the # these people are posting unless they've posted dyno graphs (or unless it's come from a reputable tuner).
EWG increases Volume Efficiency of the engine which means you need less timing to make power (or run higher timing without knock). Also it does this by reducing back pressure after turbo
Bingo! Read the first post and was going to post this as well. It reduces the back pressurre because instead of having to go through the turbo it goes around the turbo. The ones that dump into the atmosphere realize better HP because they are going straight out (like running straight pipes) Vs the ones that go back into the exhaust system. Supposedly they also make the turbo more efficient also as the air going into them and going back out is not as turbulent (kinda like porting?) and flows better. By plumbing it back in to the down pipe less gaines are realized as it reintroduces it to the exhaust flow creating some turbulence, but it still is better than the twists and turns that the exhaust has to make going through an internal WG. The other reason dumped EWG is higher hp is the exhaust is freed up (especially at higher rpms) of a volume of exhaust gasses so that the only thing flowing through your exhaust pipes is coming from the turbo, thus allowing it to be like having a larger diiameter exhaust pipe. Some people are running a second ppipe from the EWG through a small muffler to keep things quieter. Just what I have read so far on them. If I am missing something feel free to correct me.
Anyone have anything else to add or any further explaination. I am still learning about this stuff too and would not mind hearing other opinions or explainations.