Alright, I hope somone has heard of this.
I just cleand up my 302 and put it back together with a new cam. Rings and bearings. Started it up and ran it up to 2000 to 3000 to brake in cam. let off and found t he engine running rough. further investigating found that i'm only running on 4 cyl. cyl 1, 4, 6, and 8 are dead. I have spark, my valves all appear to be opening and closeing as they should (wathing them with the valve covers off while running) I have good compression. my fireing order is 13726548. I'm very confused here. I have new plugs and wires.
Has anyone seen this befor??? whats going on?
PLEASE HELP?????? I'm going to cry I just want my bronco running again.

 

Oh yea, I'm running a stock ford 2 bbl carburetor right now.

 

Not sure if this is your problem, but I found this link that discusses firing on Ford small blocks. Here's the part I found interesting:
All's in Order
Many neophyte Ford freaks don't realize that the firing order of the early 351W engine is different from the 221-, 260-, 289-, 302- and late 351W engines. The early 351W's firing order is 1-3-7-2-6-5-4-8, while the smaller Windsor engine's firing order is 1-5-4-2-6-3-7-8. What makes this interesting is that 289/302 cams are completely interchangeable with 351W cams, providing you match the firing order to the camshaft. If a 289/302 cam is used in a 351W engine, the firing order must be changed to the 302 sequence by moving the wires on the distributor cap. The same procedure is used if a 351W cam is used in a 289/302W engine where the firing order in the distributor cap must match the camshaft.

Unfortunately, this trick won't work with sequential EFI engines like the 5.0 if a 351W cam is installed, so be forewarned. According to Kaufmann, switching the plug wires will make the engine run, but power will be down dramatically. The fix is a new ECM to establish the correct injector firing order.

 

The 351W firing order never changed. It was the 302 order that changed with the 5.0 roller cam motors.
Also, there are no smaller WINDSOR motors. The 221, 260, 289, and 302 were never manufactured in Windsor Ontario, Canada.

Cheshirecat. Remove all of your plug wires and start over. Double check that your #1 cylinder (front passenger side) is on compression stroke for sure. Next line up the timing marks on balancer to TDC. Then Pull the cap off of the distributor and figure out which terminal on the cap the rotor is pointing to. Make that your #1 and go from there. Like Tom said you will need to use the firing order of the cam you installed.

 

The HO 302s both carbed and SEFI share firing order with the 351W.

Jason

 

68 351 bronc, thanks you got it. I worked on it mre this sunday and found my distributor was 180 out. When i switched my firing order to the 351 firing order it it put 4 of my wires on right and 4 firing on the exhaust stroke.
I have it all straightened out now. Thanks. the bronco is running now.

 

Glad you got it straightened out. I couldn't count how many times I just needed to walk away from a problem, get a good nights sleep, talk to a few trusted buddies and then problem solved!

 

don't i know it. i was was getting so frustrated saturday when i was trying to figure this thing out. I was going crazy. Finally i just gave up for the day. Sunday i went back to it after reading your post and just started back at step one rechecking everything makeing sure i didnt' over look something. Found it in about 20 mins.
thanks again.