I have a 12a turbo with a center iron motor mount system. I don't know what car this came in. I am test fitting this engine/mount combo with an 88 tii trans into an 89 US market convertible subframe before I mount the subframe into my 84 fb rx7. The rubber mounts are new Mazda competition FC mounts. These seem to obviously not fit into the subframe. Does anybody have any info on what car had this engine? It looks like I will be making a new set of custom motor mount brackets to fit my engine into this subframe.

 

HB Cosmo.

I'm running a GSL-SE based engine in my FC subframed 1st-gen and I have a hacked together mount based off of a left-side FC mount. The bracket breaks constantly. When I get enough round tuits, the Plan is to replace the mounts and brackets on both sides with spool type mounts. This will take a lot more fabrication, obviously.

I wouldn't worry about the mount until you have the subframe in the car. I mounted my subframe to two of the orignal crossmember studs, and my engine location is mostly OE (shifted a little to the right), I had to redrill the left side mount and obviously completely fabricate the right side mount. Same as when I had FC engines in the car.

What are you doing for a flywheel to mate the 12AT to the TII trans? If your 12AT was an automatic, that is probably more proof that the engine came from a Cosmo and not an RX-7, as if more proof was needed than the existence of the side motor mounts.