smooth out my rotor housing surface?
 

Currently doing an amateur rebuild of my Rx8 S1 engine. I've been trying to find a good guide to cleaning the rotor housings and irons without much luck.

Specifically I'd like to ask should i smooth out my rotor housings?

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If so, how is a good way to go about it?

Look in the recent threads, there's one about having this done. I see some deep groves by the trailing spark plug so the answer is you probably shouldn't. Amatuer doesn't mean cheap, So the best option is buy new ones.

If you want to be cheap, have them resurfaced. If you want to be really cheap, they could be smoothed out by hand. It is a lot of time and effort and they will look pretty decent, who knows how well they will work. IT it still is a waste of time and money. Also doing it by hand takes a lot of skill. If you had that skill then you would not be asking. By hand Expect to spend 4-6 Hours at a minimum on each housing to get a good uniform surface with minimal surface removal.

Remember the surface of there are pretty thin before you start trying to smooth them.

I also spot uneven wear towards the end of the housings, particularly in the 3rd picture.

Goopy Performance Inc. - Rotor Housing Refurbishing Services Does housing resurfacing, but I don't think yours should be going back in the build.

There is no "cleaning" that need to be done to the housings, a simple wipe down with acetone should suffice.


Also with that amount of wear and chatter marking you need new housings.

My advice, ship all of your parts to Rotary Resurrection or Pineapple racing and get them to do a rebuild for you.

Plenty of people have had good luck with goopys resurfacing...

And plenty of people have had engine failure with them.

Believe me I know it seems like a better option to get housings refinished for $600 versus buying one for $750.

But trust me new OEM is always better.

I've read somewhere that resurfacing grinds away the 'nitriding' hardened layer and significantly lowers longevity of the housing.

I wonder if there's any weight to that.

The plates are nitrided.....

the housings have a porous chrome finish on a metal insert into the aluminum :)

Thats on the Irons and yes there is weight to it...

The housings have no nitride coating they have a chrome plating to them. That process has never been perfected outside of mazdas manufacturing plant.

For a 150 bucks more a housing, why would you even think of re surfacing. I would rather walk to work for two weeks, and have new housings, than do a rebuild and go DOH!!!

It's $600 for the pair versus $750 for one new one, $1550 shipped for the pair.

dannobre/shadycrew31, thanks.
I did not know that nitriding only applied to the plates.

Free Lance Motorsports does each housing for $154. Any reviews from them?


I wonder if the folks who had engine failures with Goopy refinished housings didn't cut corners/cost elsewhere (since they were already going the cheaper route) and THAT'S why they had their engine failure...


also, if they needed an engine rebuild, something had already went wrong, and maybe that something was never fixed (oil injection, oil pressure, cooling issues, ignition issues...)