Hello I am rebuilding an 1979 RX-7 barn find and I am having issues starting it. I have put in a brand new starter motor and it turns over great as well as having good spark on all spark plugs but it still wont start. If I push start it it runs great no issues and it even idles. The carb has been freshly rebuilt and has had all emission and choke removal mods done (not by me). It has an MSD ignition system as well as MSD coils. I check the resistance on the coils and they were within the recommend resistance. Any thoughts would be great.

 

I would first start with a proper compression test with a rotary compression tester. This can be indicative of low compression. Its best to get a good idea of the engine's heth before proceeding with further diagnostics. If the compression turns out to be good, we can go from there.