Evo X exhaust observations
Thread Starter
Joined: Sep 2006
Posts: 2,331
Likes: 39
From: Hermosa Beach, CA
Evo X exhaust observations
I got to check out the X with the downpipe off. The stock downpipe is much shorter than the old one (~2 ft long) and only has a slight bend in it, but it's only ~2 3/8" diameter. So room for improvement with a 3", just don't expect nearly the same gains as was possible on the 8/9. There's also an O2 sensor at the end of it, before the cat. The cat also has an O2 sensor in the middle of it. The intermediate pipe looks to be 2.5" and has a big resonator in it.
As for the O2 housing, the exit where it connects to the DP is only 2 1/8" from the looks of it! A properly designed one with a 3" outlet could see significant gains.
As for the O2 housing, the exit where it connects to the DP is only 2 1/8" from the looks of it! A properly designed one with a 3" outlet could see significant gains.
Interesting location for an O2 sensor. I wonder if there is an O2 sensor close to the headers as well. If so, we may have a car that comes stock with a WBo2, but I wont hold my breath.
I got to check out the X with the downpipe off. The stock downpipe is much shorter than the old one (~2 ft long) and only has a slight bend in it, but it's only ~2 3/8" diameter. So room for improvement with a 3", just don't expect nearly the same gains as was possible on the 8/9. There's also an O2 sensor at the end of it, before the cat. The cat also has an O2 sensor in the middle of it. The intermediate pipe looks to be 2.5" and has a big resonator in it.
As for the O2 housing, the exit where it connects to the DP is only 2 1/8" from the looks of it! A properly designed one with a 3" outlet could see significant gains.
As for the O2 housing, the exit where it connects to the DP is only 2 1/8" from the looks of it! A properly designed one with a 3" outlet could see significant gains.
Thread Starter
Joined: Sep 2006
Posts: 2,331
Likes: 39
From: Hermosa Beach, CA
Nope, no O2 sensor. So I guess we'll just call it the exhaust elbow now. And it's f*ckin huge, probably 25% bigger than the old one. So maybe the BF exhaust elbow 
Still chokes down to 2 1/8" ID and it's non-divided. The turbine housing itself on the turbo still has the divider wall between the turbine wheel and wastegate flow.
By the way, there are brackets EVERYWHERE. Brackets bolting everything to everything! For example, compressor housing to engine block, exhaust elbow to engine block. Oh, and EVERYTHING is heat shielded! Pretty much the entire exhaust is heat shielded. And then there are additonal heat shields to protect the driveshaft bearing, etc. It's a bit crazy..... I'd plan on giving yourself 8 hours to take off the turbo and manifold.
I can see why the chasis is so stiff now too... braces everywhere coupling everything together.
Still chokes down to 2 1/8" ID and it's non-divided. The turbine housing itself on the turbo still has the divider wall between the turbine wheel and wastegate flow.By the way, there are brackets EVERYWHERE. Brackets bolting everything to everything! For example, compressor housing to engine block, exhaust elbow to engine block. Oh, and EVERYTHING is heat shielded! Pretty much the entire exhaust is heat shielded. And then there are additonal heat shields to protect the driveshaft bearing, etc. It's a bit crazy..... I'd plan on giving yourself 8 hours to take off the turbo and manifold.
I can see why the chasis is so stiff now too... braces everywhere coupling everything together.
Trending Topics
Thread Starter
Joined: Sep 2006
Posts: 2,331
Likes: 39
From: Hermosa Beach, CA
Looks to be the same as the old one. You can probably expect to see similar gains with a divorced aftermarket one with 3" outlet as you'd see on the 8/9. Sorry, no pics, but I'm sure someone else will have pics posted up in time.
With the DP, I'm going to guess that you'll only see ~1/3-1/2 the gains with an aftermarket one as compared to the 8/9.
With the DP, I'm going to guess that you'll only see ~1/3-1/2 the gains with an aftermarket one as compared to the 8/9.