When building a motor, does it matter if you have the side housings lapped before they are ported, or should they be ported before they are lapped.

Also, what about cryo-processing, i would imagine that that has to be done before they are lapped, but what about porting...before or after this treatment?

 

lap after porting, there is a good chance that at some point you will blip the surface of the housing durring porting. Lapping will only take a couple thousandths off the surface but that just might be enough to remove a little "oh #*&$!" from the surface.
I don't know much about cryo treating but if you do plan on it I don't see why you wouldnt do it after it has been ported and lapped unless you worried about warping. I don't know enough about cryo-ing to give you any advice there.

 

Doesn't matter when you do the cryo but I would do it first. Cryo treatment unlike the nitriding isn't only skin deep. Don't worry about warping that's one of the best things about cryo is that it doesn't warp the piece.

Brent

 

if you do the cryo-treating before you port it, wouldn't that make it just that much more difficult to work with? I would do it afterwards i think. Just my opinion.