i have a 1987 mazda rx7 with 13b and racing beat intake and 45dcoe sidedraft carb its been sitting since 2008 i got it running and it runs like a bat out of hell at high speed but at low speed /low rpm it misfires or something ..what can i do to fix it ive already ran seafoam in tank and cleaned carb ..i did notice it has mix match coils i wonder if thats my problem

 

I dont think the coils are a problem im using a direct fire system on my rx and if you ever hered of it it means that you can get away with only running leading
have u checked the spark plugs

 

carbs on 13b's are pretty uncommon and tend to need a lot of 'fiddling with' to get it running right. Did you run the car before it was parked in 2008?

Make sure the vacuum advance is hooked up and working, too.

 

vaccum advance? its a 87?

check the timing.

 

Neither of my 87's came with a sidedraft carb. I thought everybody that goes to a carb also switches to a distributor. Thus the vacuum advance. Maybe the OP can shed some more light on his situation.

It could also just be the behavior of a carb that cannot adjust its fuel mixture like a computer controlled fuel injection system can.

 

Post a video so we can see what is going on . Info missing here . What kind of ignition do you have ? How you mean you cleaned carb ? Gerald m.