02 housing

will a Evo O2 sensor bolt on to the apexi downpipe?

i beleive so but you better get a second opinion

It typically only works well with DPs that have a slotted flange. I'm not sure if the apex DP does. The studs are a little wider than the stock O2 housing. The angle of that connection is also different. Sometimes the DP will hit the tcase and it just doesnt work. Other times poeple get away with it. This is why RRE makes a specific DP just for use with that O2 housing. I personally dont think it helps enough to make it worth the hassle, unless you havent got a DP yet and can jsut as easily use the special one from RRE (I only run RRE downpipes anyway). Much more of the creep problem is in the turbine housing than in the O2 housing. For some more info/data check out the page on my website.