i have a 13b 4port engine REPU and it is idling rough and back fires when i start taking off. I also cant get the secondarys to open, What do i do?

Does it have a points distibutor? Or has it been swapped for an '81-'85 electronic distributor from an RX-7? What kind of carb? Thermal reactor or header? In other words, how stock is it?

We swap the distributer to a electronic one and it has headers. I think the carburator is from a 1st gen rx-7 but am not sure.. heres a 2 pix of the engine

heres the second

Well, it IS a 12A carb. I can see the stud offset and the four-screw secondary spring cover. Perhaps the carb is your problem?



Check this out. Some guy is selling a bunch of 13B carbs. He didn't answer my latest email to him, so I don't know what's going on, but here is the link. http://www.mazdarepu.com/board/viewthread....?FID=6&TID=1035