I finally got the j-spec engine running in my '87 TurboII. When the car warms up the idle hunts up n' down at about 1200rpm. When I first got the engine in it idled ok and I set the idle at 850rpm. When warming up it would go through a period of rough idle than smooth out, now it does the hunting up n' down idle.
Also, to get the timing mark close I had to move the CAS all the way over to one side, is this correct for a j-spec? On the CAS it looks like it was in the middle of the CAS all its life. I did not remove the CAS when installing. I've only driven the car about two miles (test) and it seems real strong. When I put a conventional compression guage on it, it has 100lb psi in both rotors (I know you need a special mazda guage, but I don't have one.) The engine starts right up and doesn't blow any white or blue smoke except a little blue smoke right at start up, but that stops right away.

 

Hmm maybe check your TPS. Set it after the car is warmed up.

Hmm The CAS should be in the middle. Sounds like the CAS is stabbed wrong.

I just set my CAS and TDC this weekend.

move the engine around until the right side mark on the main pulley is right under little needle.

Then pull thr CAS out and there will be a small Dot on the gear part. Line it up and then put it back in.

The needle/center section in the CAS should be set so the ends are at the edges of where the black contact boxes are on the outsides of the CAS.

A bad example will be this
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