Cjbicknell

I know it is a 74 to 78 but I have not a clue what exact year. I bought a 79 sa rx7 expecting a 12a. Next day I was home and opened the hood to see it was a 13b. I've heard there's different port sizes. Also looking for a lightweight flywheel steel or aluminum. I already have a counterweight. Thanks! Here's the only pictures I have.

rxtasy3

iTrader: (2)

the engine is 74-75. the large framed MAZDA script is the most identifying mark about these engines. i'm running a 74 engine in my 84.

Buggy

iTrader: (8)

Rotor housings for sure are 1974-75 13B. Check the stamping on the front iron to see what they say. It should be stamped 3B if they are the 1974-75 irons as well. It might be a built engine with a mixture of parts. You would need a rear counterweight from an automatic rx4 or repu to fit that engine for a light flywheel.

rxtasy3

iTrader: (2)

and i think the rear iron has R5 cast into it? there's also the letter Y in these early engines but can't remember at this moment.

Buggy

iTrader: (8)

R5 irons were used in the later 76 to 78 13b and in the SA Rx-7 12a engines along with the Y irons. They kind of mixed and matched in the days of the SA 12a. With the early script Mazda rotor housings the irons should be 3B stamped.

73rx313b

iTrader: (40)

I have a flywheel... PM me if interested

Stanford Herman

The best advice I have to source flywheel is Atkins rotary ,yes on the houseing should ba 3b stamp,that definitely SA motor

rxtasy3

iTrader: (2)

first gen rx7 didn't get 13b til 84 with the introduction of the gsl-se. 78-83 were all 12a. what he has is an old school 13b form the early 70s.