Need help on a 92 twisted wedge

92 b2200 8valve head decked 4 thou, fresh performance 3 angle valve job, stock rocker assembly, fuel pressure regulator {@3psi like tech told me}, weber 32, new plugs wires cap and rotor, 100,000 volt coil, 271/400 cam, pacesetter heddar,31 inch glasspack,{no tailpipe yet} stock pistons down, correctly timed correctly assembled. {new water pump too for kicks}

It seems like it is only running on three cyl. it has spark, good compression, good plugs and im totally confused why it runs so rough. Mabey I overlooked sumthin obvious.it starts great {1 rev} It will go down the hiway but smokes between gears. No backfires pops or hesitation. it does run-on a little when I shut it off If u can help out it would be greatly appreciated. Im in central IOWA so it is on 87 octane. does it require 92 octane now?

If you have an electric fan, and it's wired in improperly, it could cause the run-on issue. Also... if you aren't running a relay in the fan circuit, it may be robbing power from the coil.

the truck is still running the manual clutch fan...thanks for the advice

running on is usually caused by hot spots in the combustion chamber. Are you sure the camshaft timing and ignition timing is correct and the ignition advance is working? What spark plugs are you using?

My old ford runs for a sec after its off sometimes. Pretty sure mine does it because occasionally the float sticks and it gives it too much fuel

Thanks.... Ruled a couple things out today gunna reset float and test pulse generator in distributer in the morning... Probly new wirescapnrotor too NGK r plugs good timing and perfect vac advance
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When you pull one spark plug lead at a time out of the distributor cap, with the engine running, replug, move to the next until all four have been done.

Does the idle speed change on any cylinder? If so, that is the problem. Trouble shoot it, to rule out electronic spark delivery to that cylinder problem.

If not, this is not the problem.

thanks for all the help we got it running all is good in twisted wedge I'll give an update later

apparently o Riley's sold me a bad spark plug(thanks jerks) ... we freshen up the whole ignition system replaced a bad spark plug and now I have a beast on my hands guess it's time to start shopping for rims and tires because the ones on the back of it are not doing the job now

Bad plug or installer who did not check the gap of every plug before installing?