'86 720 carb'd 4x4 having acceleration issuses..HELP!!!

[BootstrapBill]

My '86 720 z24 carb'd 4x4 falls flat on its face on hard accleration till it hits about 3k rpms then takes off like a rocket. I'm new to this truck, and nissan in general, (chevy man) but i need some help fellas. Ive replaced the spark plugs, both coils, wires look good, carb seems to be working fine but not 100% sure. Idles great, e- choke.works, no visible vacuum leaks, not possitive if secondary is opening up, or if acceleraterpump is working properly. Truck stumbles on light acceleratiin, and falls hard in normal to hard acceleration, but pretty consistant on around 3k rpm and up. Just picked up a carb gasket kit to rebuild the factory carb next, but any and all suggestions/advice would be helpful! Thanks in advance!

[Rev_D21]

I'm going to move this to the 720 section. We have a great group of guys there who will be able to get you going in the right direction. Since the D21 trucks never had carbs you'd be better off in the 720 sections. Welcome to NICO!

[BootstrapBill]

Thanx rev

[Tpanda]

Thanx rev

is it a stock carb?

I just put a weber 32/36 on my truck and under hard acceleration it falls on its face until it hit higher rpms. I think my truck is just a fuel regulation issue, too much fuel under hard accel.

[BootstrapBill]

Yes stock carb. It almost stalls out and sputters till it reaches 3k. Then it has lots of power and runs like a champ. Not too sure on how this duel ignition system works, is one side for low rpm and the other for higher rpm?

[breadbox]

no, dual spark is for emissions only. the exhaust side is a waste spark to aid in the burning of unspent fuel.

[BootstrapBill]

Oh ok, i see... thanks for clearing that up for me

[Tpanda]

i think first step would be plugs, wires, cap, and rotor buttons.


That would be my first step. May have carb issues though, Im sure a more experienced member will chime in.

[BootstrapBill]

It kinda seems like it might be dumping too much fuel, if that were the case should i change out the air/fuel mixture silnoid?