i have a 1983 rx7 with a stock nikki (pretty much everything stock). the car ran horribly when i got it, so i switched out the carb with the one from the parts car and it ran a lot better. since then i replaced the fuel filter, distributor cap and rotor, spark plugs, wires, hoses, radiator, thermostat. now this carb has been hesitating a lot when i floor it; to the point where if i dont let off, it will die. also, as of late, it tops out at 6000 rpm....

fuel pump? or is the carb in need of a total rebuild, including the ap? ive tried adjusting the ap to no avail, and its a cali carb so i cant easily adjust the mixture so im hoping its not that....

another thing is when i let off the clutch in neutral (or in gear), there will be a sort of ..knocking sound that occurs (it gets faster and louder if i push the gas)...it dissappears when i push in the clutch all the way thou....throwout bearing???

 

Make sure the fuel pump is in good working order by pulling the fuel line that goes to the carb (left side of carb if you are sitting in the car). Make sure the vaccum secondaries are working properly. Do a search on how to check the secondaries because mine are mechanical. If the secondaries do not work, the car will never pull max rpm's, and it will always feel kinda slow. As far as the sound when in neutral, the throwout bearing is toast. I would wait and replace the clutch along with it since the trans has to come out to get to it. Hope this helps.

 

You know, I had a very simaler problem with my '83 Gsl. I could never found out what was causing it until I did the rats nest removal. I found out there were two vacuum lines going into the basplate under the carb swapped. If you arent planning on doing a nest removal, may I suggest a Haynes manual that will have a complete vacuum diagram with pics and troubleshooting guides. Good luck!!!!!!

 

i had similar problems with my 83 GS....may it R.I.P. for now.......carb rebuild helped and i agree that you need a new throw out bearing. this would also be a good opportunity to replace all of your vacuum lines as they are probably getting a little brittle if they have not been previously replaced.

aint the CA nikki carbs a pain in the ***?