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Acceleration studdering

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Hey all!

Here is my issue. I've been working on my 73' 240Z lately and it's coming along nicely. I did a little carb work and got my choke working properly but now when I accelerate from low RPM's there is a hesitation before the car accelerates. If I'm moving along nicely and then press the accelerator it accelerates just fine. I added oil to the carbs (Automatic transmission fluid) because the piston in the carb was hard to lift even with my finger. Now the action is nice and smooth. I don't know if has anything to do with it but the rear carb (round top SU's) seems to slick a little after it falls all the way down. Could the needle be causing it to stick when it drops?

*BTW, to anyone that complains about your gas pedal being stiff at first... After I changed the oil in the carbs the gas pedal is now nice and easy without the stiff action and then the hard acceleration that comes from the throttle then being wide open.

Thank you everyone for your help!

Is your timing set right? If you're just starting to accelerate and your timing is off, this can lead to sputtering, or at least it did when my timing was way off.

The fact that the rear carb sticks at all is not good. It should fall smoothly and end in a "clunk" sound and not stick at all. It is sticks the needle is no doubt hitting the nozzle. This could be due to the fact that the carb dome is slightly off center. This can be fiddled w/ by unscrewing and then screwing down the dome in a different order and torque. Play w/ it a bit to see if you can get it to stop sticking. Are your carbs sync'd? Did you check your spark plugs, timing, valves, etc?

Bill

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