I just picked up a 1981 Mazda rx7 (12a) last week as my first rotary. I’ve had issues getting it running from ignition problems to vacuum leaks. My final problem is a fueling issue. I took the top lid of the intake off and looked down into my primaries while I took the car off of idle and through the rpm range and saw that my rear rotor was pulling more fuel than the front and is fouling the rear plugs and causing the car to misfire and stutter while driving EXCEPT at wide open throttle. The float levels are identical it’s the stock Nikki stripped down and the jets are all identical.

 

Needs a rebuild. Pull it apart, clean it all up real good, blow out any holes with compressed air. Reassemble. Keep old needles and seats and don't try to add new gaskets to the plastic spacer between the intake and the throttle body. Check all vacuum lines and replace as needed.

 

Man you guys make it seem so easy, i need a rebuild too =/

 

I can vouch on the rebuild. everything flows better (even visusally). and it's just nice to know everything is right.... definitely worth the 120 dollars