I just picked up an old 12a that was in an rx3.

As I am getting it ready for service, I need to know how to get a water pump and if there is a whole additional housing for it like the later models.

Also, the inner edge of the front exhaust port is beat to hell,, but the inner area by the rotor looks good and actually looks a little ported. Should this be of concern, or should life continue as we know it?

What is in the center top of the motor with an electrical spade terminal??

Why does it have no mazda markings, only nsu-wankel in the rotor housings castings? are parts of this pre-mazda, non-mazda?

If this thing is street-ported like I'm told, what are my most cost-productive upgrades for power and what should I expect out of one of these older beasts.?

Thanks

 

For the water pump, Yes there should be 2 pieces to it. there should be the cast housing and the actual pump. for the pump itself i would check a local auto parts store, they might be able to get one. If you dont have the housing, that will be hard to find. I think i have one that i would sell for $10 plus shipping if you want it. As for the housings not having mazda on them, i dont know, they are still mazda but just dont have the markings. mabe it was a licensing right issue or something.

Yes i would put a big street port in it. then the best upgrades will be getting a good header and exhaust and a good intake set up like a good weber, I highly recomend a 48 IDA as long as your not concerned about milage and you dont live in a very cold climate, (no choke). Get some good MSD blaster coils so it run smooth and starts good. If you have the money light flywheels help acceleration. Electric fans help to and a good cost saving way to go on the fans is to go to the junk yard and get one out of like a v6 taurs or something, and they work really well. With all these bolt ons the engine should be able to put down around 130-160 RWHP. Pretty good if its in a light car. By the way whats this going in? And why are you so bent on using the old engine and not a newer early 80's? the newer engine will be easier to get say a water pump for, all the ports in the engine should be bigger stock, and the rotors will be lighter and higher compression in the 83-85 engines.

CJG

 

I'm not bent on using the old 12a, actually I've got a 90 model 13b that I was wanting to use, but this 12a found its way to me already ported and rebuilt, so it seems like a good candidate to jumpstart a stalled project.

Its going in an opel gt, so I figure if I make sure to use about a 1 inch spacer in my mounting setup, I'll be able to use the 13b later if for some reason I crave more power.

 

You have probably picked up a twin distributor engine.
They don't have Mazda on the rotor housings but it is a Mazda engine.
Does it have two separate distributors ?
If you can see the apex seals through the exhaust port, are they 6mm seals ?
If it is an early top starter engine, it will require a different transmission than your 13B.
Don't have a picture ?

 

the front cover has been replaced for a single distributor and while i'm not for sure, I don't think the seals are 6mm, I guess I can check. the stater is not the top mount.