O2 housing revisited

[cheekychimp]

Took a week off work to start doing some groundwork to finish my car ... yes really!

Anyway this is an old thread of mine about the O2 housing I bought click

I had the recirculation tube welded but the guys said the stainless was too hard to be able to tidy up anymore. Well I didn't really believe that and so I bought myself a Dremel 4000 and spent about another $40 on tool/carbon steel tips for it. I spent about 15 minutes on it today just to prove to myself that it can be tidied up. I forgot to get myself some goggles so I packed up before I got some shavings in my eye. I think I can tidy this up quite well and I may well pull the turbo and port/gasket match it as well.

Anyway the question is this,



This area is easy to clean up, just grind back and blend because you can do it without affecting the flange thickness.





However because the pipe here comes in at an angle if I grind back to blend the flange into the pipe and remove the 'lip' it will significantly reduce the thickness of the flange at the edge. Should I avoid doing that and leave the lip in order to preserve the flange thickness?

 

[EMX5636]

You can take the corner off the flange in the bottom picture. I've done it on a few O2 housings and never had the flange warp/crack there.

 

[cheekychimp]

Thanks! I'll get some goggles and spend a day in the garden with a cold six pack doing this next weekend.

 

[4thStroke]

Honestly, the difference in flow won't differ much from drop through from the weld. As long as the bung isn't dropped through the hole in the O2 housing, you should be fine. If I bought that piece from a reputable manufacturer, I'd expect it to be taken care of, though.

You'd be amazed at what we can port with just a die grinder and the proper bits. The biggest part is to smooth out the areas that wont hurt the welds, that way you retain strength and longevity.

 

[JNR]

Too hard? lol, guy must not had the right equipment...You just have to go slower on stainless is all. I used a rotary file and a die grinder to do mine w/o any issues, then followed it up with some flappers. I normally wouldn't recommend a dremel for anything like that, but sounds like it worked.

I think I linked my before and after somewhere on either of the O2's I redid, but they came out real good and are 100% port matched and blended and it's the details like that, which are totally worth the time and effort. It's good you fixed it and hopefully you enjoyed that, like I do (working on that stuff and fixing other people's "work").

 

[cheekychimp]

Quoting 4thStroke:
Honestly, the difference in flow won't differ much from drop through from the weld. As long as the bung isn't dropped through the hole in the O2 housing, you should be fine. If I bought that piece from a reputable manufacturer, I'd expect it to be taken care of, though.

You'd be amazed at what we can port with just a die grinder and the proper bits. The biggest part is to smooth out the areas that wont hurt the welds, that way you retain strength and longevity.



Spencer you aren't the first person to say this actually and I do believe it. There is PROBABLY more power to be made by adding a pound of boost than smoothing out those welds. That said FFWD has a coating for the inside of the O2 housing to further reduce heat emission onto the alternator. I've had it done on a cast housing. I am just not sure if that will adhere better or worse to a rough surface (similar to the casting). I think it will be better to grind away any obvious ridges etc but I'm in two minds as to leave a coarse finish or go to a another tip and smooth/polish after that.

 

[EMX5636]

Quoting JNR:
Too hard? lol, guy must not had the right equipment...You just have to go slower on stainless is all. I used a rotary file and a die grinder to do mine w/o any issues, then followed it up with some flappers. I normally wouldn't recommend a dremel for anything like that, but sounds like it worked.



Biggest suggestion I have is to use grinder grease on a good quality metal grinding/porting bit. I stopped using stone except for polishing a while ago.

Oh, and EDIT- please wear glasses or a face shield... Advice coming from someone who has gotten things drilled out of their eye.

 

[JNR]

Good point about the eye (especially) protection and I usually use a full face shield when I grind and sometimes a respirator with it (alum. dust especially is bad news). Unfortunately my shield broke at the mount (ugh) so need another, but haven't done any of that stuff for awhile.

I typically always lube my tooling and pieces (esp. on the lathe) and it keeps them lasting a lot longer plus reduces the heat; stainless is some hard material and creates a heck of a lot of heat, even going slower....while I have a crapload of burrs, files, bits and so on, they are $$ so I try to keep them as long as I can. A sharp tool is important for good results and less heat too, as I'm sure you're aware.

As for stones, I rarely use those, except on a bench grinder and prefer flapper wheels for the middle polishing, so to speak...super fine "scotchbrite" is my preference though, as it doesn't load up like paper and gives a really nice finish.

another nice thing to have and I need more of is cutting discs, but on a dremel they kind of suck unless you keep them perfectly straight...don't know how many I've broken no matter how careful I am, lol.