first of all the timing.. its an 1996 Explorer engine but i swapped the timing cover from an 1990 351W and used the balancer and marker of an f150 5.0 since i cant use the of of the explorer becuase it didnt match up the belt system.. i set the timing at 15 btdc but i somethimes it backfires from the carb and shoot a flame! do i need more timing?? or less?

am i doing it right?? i didnt remove the vacuum line to the billet pertronix dist and i just set the timing at 15 BTDC should i set it at 18 ? or try 10 and see if it backfires ???



about the miss its been around for a while.. i think the sparkplugs are to blame becuase i have them gapped at 0.50 the miss was not present when the sparkplugs where new but now they have about 100 miles and it misses at rpm 1000 to 1500 and very little above that.. but at WOT it does not miss

First off, always set the timing with your vacuum advance disconnected. Also, make sure that you hook the advance up to ported vacuum, not full vacuum.

Does it crank slow when it's hot? If so, that is a sign of too much initial timing.

surewhynot said:

First off, always set the timing with your vacuum advance disconnected. Also, make sure that you hook the advance up to ported vacuum, not full vacuum.

Does it crank slow when it's hot? If so, that is a sign of too much initial timing.

Click to expand...

thats what i did wrong.. i set it with the vacuum connected.. no it always cranks the same


i set the line to the small tube on the pass side of the holler the one closest to the intake manifold.. i lost the instructions i gotta go online and see if thats the one for the dist vacuum

If that is the lower one, it is full vacuum. You need to put it in the higher one. What is happening now is it is pulling full advance when you idle, because the vacuum is high. As soon as you hit the gas, the vacuum drops, and the advance stops advancing. Your ignition is retarding as soon as you stomp it.

eek :O gotta fix those tomorrow ! lolz

You might find you gain some power when you start out.

surewhynot said:

Does it crank slow when it's hot? If so, that is a sign of too much initial timing.

Click to expand...

Is that the same as hard cranking?

Yes, you could call it that. The engine turns over slow, like the battery is low.

how could timing cause the engine to turn slow?

If the timing is to far advanced then the spark plug is firing when the piston is on the up stroke, being as the motor is turning slower, it happens at the same time but the momentum isn't there to keep the motor going... So the starter is fighting to get the motor to spin fast enough to start...

Thats how i picture it in my head...
But honestly its a wild a$$ guess.

You are correct Don.