Engine runs like crap, HELP!

[DBLSPRT68]

OK, Here is the deal. I need to drive this truck Saturday a good 40 min. to a swap meet. Not to sell the truck, but lots of parts I have laying around. I've had this truck about 4 years and never checked the timing. It ran great, so never checked. :p I just changed the intake, and put in a new Accel dist(hei). Now the engine runs like Crap! Just before I did this change, I tried to check the timing, wasn't in the area of the timing mark at all! Drove the truck and it ran great. So now, even at rough idle, the timing mark is on the other side of the balancer. Could this engine have ran great with a dist. 180 degrees out? If it ran good then, and I put the dist. rotor back in the same spot. Why won't it run good now? Any Ideas would help. Also, what is the factory timing setting on a 82-85 350 M code?? my sticker is gone. David

[Prerunner1982]

could also have a bad seal on the intake causing an airleak...

[DBLSPRT68]

Here is a little more info. Standing at the rear, the exhaust sounds like both banks are misfiring. I have true duals, no crossover. I did this job slowly and made sure it all went together well. I also put on a 3/4 inch carb spacer. I thought about vac. leaks, so I put my hands over the carb, and it died. So that means no vac leaks right? I'm asking for help because of my timeline and my job. I work 10 hr shifts, so I only have a few hours a day to figure this out. I still need to road check it, because of all the other stuff (non engine) done to it. I will check again with starting fluid for vac leaks tomorrow. Any other suggestions? David

[RockHQ]

1. Did you disconnect your vacuum advance when checking your timing at idle? Do it (and remember to plug the vac. port you're using) and recheck. Set to 8-10° BTDC for a baseline then fine tune from there. Just because you have the rotor pointing at the same direction than with the old distributor does not mean your distributor cap poles are aligned the same way, or that you have the dizzy housing oriented the same way.
2. Double check your plug wires (firing order!)
3. If you converted from a points ditributor you can not run power to your HEI from the old coil positive (15) wire, because there's a resistor to limit voltage (prevents excessive points contact wear), you need to have full 12 volts to your HEI distributor. You can do a quick check by running a jumper wire from your battery positive to the HEI bat-connector, then see if that helps. You won't be able to shut off the truck from your ignition switch so you'll need to pull the jumper wire.

[DBLSPRT68]

After doing research on my own, and help from ROCKHQ (thanks), I have my truck running great again. In case someone wanted to help on this issue, don't worry it's fixed.