Firing order

[hill9303]

I was working on getting my boat back together after putting new manifolds on it last night when I became perplexed at the spark plug wiring. What is the firing order on an 86 PCM 351 and how are the cylinders numbered? The dude before me put an edelbrock intake on it so I have no idea how it is numbered. The way it is wired now (the right bank wires werent removed). The firing order on the engine tag doesnt follow any numbering scheme I can come up with. Could it miraculously run with a different plug configuration?

Thanks,

Dave

[Brian Raymond]

The firing order for the 351 is 13726548. 1-4 are on the drivers side, and 5-8 are on the passenger side. When looking down on the cap from the front of the motor, #1 should be around the 11 o'clock pos. and go clockwise. Brian Raymond

[hill9303]

Thanks for the help.

[awesomesteven]

Sorry, but I had to revive this thread because I've read different things.

I have a 86 sunsport with a 351. The firing order is 13726548. Looking at engine from the front 1-4 are on the drivers side and 5-8 are on the passenger side.

Here is what I see different. Brian Raymond (2 comments up) says looking down on the cap from the front of the motor, #1 should be around 11 o'clock position and go clockwise. Shouldn't it be counter clockwise since the engine is a LH turning engine?

[michael hunter]

Firing order 13726548 Left 18456373 Right . Yours should be a left engine.

http://i303.photobucket.com/albums/nn127/suprahunter/Picture028-2_zps82d91482.jpg

[jtryon]

reviving an old thread:

i had my carb rebuilt this spring, and changed out the plugs, wires, cap/rotor and points as well. i'm having a problem with the boat not wanting to rev over 2300-2400 rpms now, and have looked at the firing order which is correct, and every picture of the cap orientation that i can find online. i'm still at a loss after 5 hours working on it yesterday. when i did the plug wires i did them one at a time to make sure i didn't cross one, but now i'm wondering if i started in the wrong dist cap location to begin with, or something else stupid.

for reference, the boat starts great and idles great. dwell is 31, timing at 10btdc, and advance around 580. when i rev the engine the timing goes to about 20.
battery voltage is 12.7 with the engine off and 13.1 while running.
i'm only getting 4.5 volts at the coil with the engine off and 3.5 while running.
12.6 volts at the ignition switch in the off position, 11.7 in the on position.
13.2 volts at the ballast resistor hot side, a little under 5 volts on the pink side.

all that being said, here's my question: i have a screw-down cap, not a clip-down cap ('88 sunsport, 351w). when i look at my dist cap from the top, the front screw has the 6 and 2 plug wires on either side of it, and the rear screw has the 8 and 1 wires on either side of it. can anyone confirm that this is the correct orientation for those wires? i'm starting to wonder if they are off by one wire or something.

[chris young]

Easiest way to tell is bump the engine to TDC and pull the cap to see where the rotor is. You might have to do it twice because the cam rotates once for every 2 rotations of the crank, and thus your rotor could be 180 deg