The O2 housing is the pipe that connects the turbo to the downpipe. Since it is also the pipe that the wastegate dumps into it is very important that it is smooth flowing. The one on the evo is one of the best ones David Buschur has ever seen on a stock car and he said it doesn't need upgrading untill you are making alot of horsepower and most likely upgraded it during a turbo swap. The install on this part is very hard due to removal of the radiator. I've only seen 3in aftermarket versions and downpipes that have this housing included in the construction of the downpipe like RnR racing uses.

Hope this helps. Anyone else want to throw something in feel free

Guack

 

I just went from a 2.65" HKS dp and 3" cat-back with test pipe to a Helix 02 housing and 3" helix dp connected to the same test pipe and cat-back. It breathes ALOT easier in the upper rpms now. Very noticable gains on the butt dyno.

Helix 02 housing was easy to install. No need to take the radiator out if you have a decent set of tools. You may need a swivel attachment for a socket wrench to get one of the bolts off the old o2 housing, but that is it for special tool requirements.

 

i'm going to bump this cuz it was very informative...

also, i was wondering if it in any way is restrictive like the cat conv. is? could one just get rid of the o2 housing altogether?

 

You still have to run the O2 sensor itself and the wastegate still needs to dump its exhaust somewhere. You can get a downpipe which has this section included in its construction. Check out the RNR O2 elimination downpipes compare the pics of these style Downpipes vs a standard one made to run with an O2 housing

 

what i meant was, what's so special about the o2 housing? does it DO anything that is purely for emissions (which is not my concern)--that is, could you replace the o2 housing with a "straight pipe" kind of thing?

 

hueman, it is essentially a dual-inlet pipe with a single outlet and an o2 bung. There is nothing more to improve/replace short of making it bigger/smoother.

 

OHHH... i got it... i was imagining it was some kind of filter or something for emissions. thanks!

 

At the last dyno day I attended, there was a car with a turboback + cat and another identically equipped with a dump back+cat. Other than that, they had cam gears and XEDE. There was not really any discernable power difference between them. FWIW at ~350whp and down, a test pipe will make a lot more measurable whp than an upgraded O2 housing IMO.

Cliff's notes: Dynos agree with David and Guack.

 

This is good info. I am about to get the Helix o2 housing. So do most people think this was a good mod or just a waste of money?

sir luks alot what other mods do you have on your car?

 

I used one for a few weeks, noticticed quicker spool and a little more top end, had mine ceramic coated, not hard to install, but it is easier without the rad in. It is now for sale in the for sale section(upgrading turbo).

 

For me, it worth the money. Topend more smooth and strong. Alot of people saying it is waste of money blah blah blah... but i can tell the different after i install it

 

everybody says this part is easy to install, but i cant get mine off. the bolt will not move!! anybody got any iteas???????????

 

WD40, patience, elbow grease, and prayer.

 

I think it would be a good piece to have installed. Then you could have a TRUE "turbo back exhaust"

 

haha, prayer always seems to work!!! He is just making me work for it this time!!