It makes me laugh and cry at the same time. I bet you could have gotten a good deal on that old sled too. Wonder if it had a rotary in it? Poor Rx-4.....

 

I am yet to figure out what the point was....

 

OK so seeing that the motor only had 70,000 miles on it I decided this weekend to pull it apart and see if anything is still useable. Everything looks good except for the housings. the Irons are flat and smooth with no major signs of wear. The housings have chatter marks and some flaking on the edges.

Can I just buy new 13B housings for my motor or do I have to find some oldschool ones?

Rear rotor had chatter and some wear



Front rotor had flaking and wear

 

If you buy new housings, you will need to switch to modern irons. Old school housings have the coolant o-ring grooves in the housings and flat irons, newer 13B housings (86 and above, the only ones available from Mazda) are flat and have the grooves in the irons.

If you need new housings, then you probably should use 4 port modern irons. Or, depending on how you want to port, 6 port irons.

Another option is to buy new housings and have the grooves machined into them.

 

Crappy
Yeah I think I need new housings.. these ones are definatly iffy to say the least.

I will have to look around town and see if I can find a machine shop that will groove new housings.

The Irons I have are in awsome condition and it would be a shame not to use them

 

I'll take those housings for the cost of shipping.

 

I am not to sure you want them, I am sure they are reusable but definatly not ideal

 

From the pics those housings don't look all that bad. Like you said, useable but not ideal. Old school housings like those are not easy to come by, but every now and then a set come up for sale. Keep your eyes open on ebay and on the forums. Machining those grooves would probably be a pain the the hind end, and you won't have the cool old Mazda logo on them.

 

The set I'm going to to use in my friend's rotary baja are in worse shape on the chrome. The aluminum is ok.

Do yours have any pitting in the aluminum?

 

I don't think creating the grooves would be too bad. They don't have to be precision, just in the generally correct area. Any good machinist should be able to figure out a CNC program quite quickly. But best find a friendly machine shop that likes doing weird stuff otherwise the setup cost will be too high. I've never had this done myself but did consider it for my Cosmo until I found out that the housings were perfect.

 

Those grooves would have to be more precise than you would think. If they got too close to an edge it could crack out and cause a leak. It is doable, but you would for sure have to find a machinist who is cool with little tedious projects like that.

 

Will RX7 housing from the 84-85 GSL-SE work? IIRC, they have the grooved rotor housing.

 

yes and yes that all pre-86 motors (12-A and 13-B, 4port and 6ports) have the grooves on the rotor housings. for the plates, they are all the same and are interchangeable

 

If I was to use the housings from a gsl-se what rotors would it be better to use the 4 port rotors or the 6 port rotors?
Probably going to boost this engine at some point.. run it N/A for awhile then boost it when the time comes so I am thinking use the 4 port ones

 

The original 4 port ones should have 3mm apex seals already which would be nice in a boosted application. I don't know much about the GSLSE rotors though.

 

In the current economy, you'd be surprised how many machinists are willing to take on a small weird job just so that they can at least start to justify their coordinate machine and CNC mill. It's a whole different world then a few years ago. What I meant with the grooves is that 0.5MM is about all the precision required, which is easy to do for any machinist. Most will be far more precise then that anyway. Still, the whole operation is probably around $300 and combined with two new housings, brings the bill to over $1000. Likely not worth it in most circumstances.

Earlier 13B rotors are 9.2:1 compression, GSL-SE rotors are 9.4:1 compression. In the real world I highly doubt there is much of a difference. If the GSL-SE rotors are in good shape then I'd use them. But if the RX-4 rotors are in better shape, I'd use those.

 

Yeah Aaron the rotors look to be in good shape. I just got some history on this car this morning. The previous owner was up from the states driving through BC and lost all spark. No one could figure out what the problem was so it was abandonded.

Any how I have found a couple used housing for sale and they look to be in pretty damn good shape. I am a little worried about 1 housing as it looks like it had a real hot spot right by the trailing plug. Does this look bad or is it fairly normal?



And on a final note I went to the body shop yesterday after work and was able to snap a couple pics on my phone.
Ray has 99% finished making the inner frame rail, all thats left is to notch it for the sway bar and add mounting holes for the cross members and such. I will be going back today to take better pics as everything should be welded in and the frame rail should be done

 

Those housings look pretty good. The small amount of extra wear near the trailing holes should be fine with OEM apex seals. It will take a few miles to break in, but less than 1500 (unless you change your bearings too).

 

Thanks Jeff I think I am going to buy all new everything for inside this motor. i will get some measurments for you tonight.. that link you sent me was awsome!

 

That's not a hot spot on the housing, just a funky reflection from the flash.

I can try to get a better picture if needed.

 

No need pm'ed

 

I'd say those housings look good man. Your body guy did nice work on that frame rail too. You owe him a beer or two!

 

he can buy me a beer with all my hard earned cash he has in his pocket lol

 

Well no major update today they are just picking at things while the frame ril is out taking care of any ugly little spots

Ray did finish putting in nuts reinforcment plates and notched the frame rail for the sway bar

here are a couple pics from my phone of both old and new

 

Thats some NICE work he's done. That takes talent.....and CASH. Want one of these still, in coupe or wagon form. Considering the 74 GTR I know about.....I will be ton of work, but its almost complete.....