Hi,
I found a 13B NA engine and transmission on ebay from Texas. I know very little about first generation rotaries. Upon closer inspection as I disassembled it I noticed differences between what I recieved and what my 1988 GXL have.

First thing I noticed was that the bellhousing does not have a vent! Found out on this site that I have a FB MT instead of a FC MT. Does anyone know if they both have the same length and can I use the FB without any modifications like a custom driveshaft?

OK, that is one concern, the big one is can I rebuild this engine and swap it with my 88 FC series 4 engine, they seem to be a match but.......

The picture above shows what appears to be a manufacturing defect with the left injector borehole. The right hole had a diffuser that popped right out but the left hole diffuser did not want to come out to the point that I crushed the diffuser into bits trying to remove it. I scraped down to metal and noticed that it was not smooth or as deep as the other bore! Putting a nail through the vacuum holes showed that the left side needs to be much deeper and the bore larger to accommodate the diffuser.

What am I seeing?

Thanks,
Gary