diabolical1

Hi All,



My rotor housings should be coming back from the machine shop tomorrow, so I will then need to proceed with what I imagine will be an arduous task of installing, welding and contouring the sleeves. Well, unfortunately I don't weld (at least, not yet) and the person that will be doing the welding for me said aluminum (my sleeves) can't be welded to steel (the inner surface of the rotor housing). I took his word for it, so ...



My first question is how do I go about treating the face of the port? I figure even at my best, I probably won't get the contours 100% perfect which will mean gaps - even if they are small. I'm not worried about the sleeve moving since it will be secured three ways. First, it will be welded on the housing. Second, the epoxy in the water jacket. And, third, the sleeve will actually be braced against the housing because I had the inner hole cut closer to the inner diameter of the sleeve. However, I was kind of counting on the weld beads to help me with the gaps, but since there will be no welds at the inner end ... my concern is what will the gaps (whatever size they are) do to airflow?



Anyway, I imagine I will have more questions in the near future as I get these housings ready for assembly. So please, any of you that can impart any assistance, experiences or advice, feel free. As always, I appreciate any and all help.



Thanks,

1

Lynn E. Hanover

There is no need to weld the sleeve to either the inner or outter wall of the housing. It would be nice if the inner end of the tube were a light press fit, to keep the crome from cracking when the block is torqued up. You may deftly slide a fine file along the edge of the housing adjacent to the port, so as to lighten the pressure where the sleeve passes through. The inner wall only. I break the chrome and a bit of the iron with a diamond file, to keep the chrome from flaking.



Just one or two thousandths at the most. It won't leak anything either way. Don't worry. The only other thing is that none of the tube can stand above the chrome sealing surface.



I used Aluminum filled Devcon epoxy. It used to be called Devcon Plastic Aluminum.Works fine didn't crack. I never used anything else, so I cannot comment on any other brands. I filled the water passage up solid where the sleeve goes through.



It will run cold right there. No cooling is needed.



With 100 PSI of oil pressure, and the high rev mods, a big Pport 12A can do 310 HP at 10,000 RPM. A 13B needs more bearing mods, but can do 330 HP at 10,000 RPM. Milage will be dismal. In road racing don't count on more than 6 MPG with 44 MM chokes or similar.



Send me a private Email and I will make some drawings for you.



Lynn E. Hanover

diabolical1

as always, thanks for the reply, Lynn - and many thanks for the drawing. i will do my best to follow your instructions. as it turned out, they hadn't even touched the housings when i called today (a day later than he said they'd be ready). needless to say, i was quite disappointed so i went and picked them up. i won't be home for a few weeks and wasn't going to risk leaving them there. i kind of doubted their understanding of what i needed anyway, so maybe i dodged a bullet. okay, i'm rambling ...



on another note, remember i'm building a semi-peripheral 13B so the holes won't be nearly as big as a full peripheral. from your reply (and e-mail) it sounds like you're thinking i'm building a full, all-out peripheral port. the sleeves i'm using are 32 mm (1.25-inch) in outer diameter. i wanted to keep it fairly small simply because it'll be easier for me when designing my lower intake manifold. with that in mind, do you think i run the same risk of cracking the chrome when i torque the tension bolts?



anyway, i just wish i had access to the tools necessary to make the holes myself. the anxiety of getting this engine underway is killing me.



thanks again,

Jason

Lynn E. Hanover

No probably not a factor with a small port.



Lynn E. Hanover



Anyone know if there is a lifetime limit on posting pictures? My attachment editor says I have used 29.35 Meg of 29.30 and I cannot post anything. Is this correct?

j9fd3s

i ran into the same thing, took a while to figure out



i guess there was an update that only gives you a certain amount of space for attachments. up at the top header, if you click on "my controls" and scroll way down on the left theres a "manage attachments" thing. if you click on it, its a list of every picture you've posted.



you'll have to delete pics, to post new ones as theres only so much space now

diabolical1

well here's an update for anyone that's bored or cares ...



after all this time, i was able to make a little progress with my semi-peripheral project. it's amazing how some things just come to you seemingly out of nowhere. at any rate, i was able to fashion a template. i have a few refinements to make, but i was able to get the outer holes cut last night. i just need to make a template for the inner holes now and then machine the sleeves and i should be good to go.



will post again whenever i get to do the next phase.

diabolical1

well, i just cut the actual port a few minutes ago (almost 0200 EST) and everything seems to be fine. for those wanting to try this for themselves, precision is a requirement and without the right tools, it's better leaving it to a professional if you want perfection. however, for my purposes: (1) getting off my *** and into the game and (2) research and development, i can live with small lack of precision o have because i don't have the right tools. i did much, much better with my actual port template as i was able to learn from the mistakes made with the outer one. i'll verify the timing with my timing wheel when the sun comes up and in all honesty i expect it to be a little off between 1 and 2, but it's the price i pay for not knowing anyone and not having a large budget. i can live it. it's a labor of love.

diabolical1

okay ... it's been a few weeks since i got the ports cut and i've been working on and off on trying to machine the sleeves. i've come to the conclusion that i don't have the tools to get the shape to perfectly contour the housing, so there are some gaps. i just hope that when it's all said and done the epoxy won't chip or flake or whatever it can do to leave me with pieces of it getting sucked into the motor.



anyway i don't know crap about epoxies. so what i really want is an opinion on the epoxy to use.

i've chosen this: Devcon Aluminum Epoxy



any thoughts?

Heath

Looks like we are in the same boat. I also have a bit of a contour issue and some epoxy exposed next to the sleeve on my full pp. First pp, not thinking clearly, dumb mistake that won't happen on the next motor (Install the sleeve before porting the housing to mazda factory pp timing specs...lol) . My engine is assembled but I haven't completed the project so it hasn't been started.

My epoxy of choice-- Devcon aluminum for the rotor housings and Devcon plastic steel for the side plates.

I have a huge aluminum radiator I'm hoping will help keep temps down but I won't be surprised if there's a failure since the epoxy will see a bit of flame from the overlap.

Live and learn