1977 Chinook 20r w50
got rid of the emissions and smog
single port off the dist to the right port on fuel/air mixture screw on original carb
now doesnt run and back fires bad

Did run (barely) before tearing it apart
Bought new Mahle Headgasket kit and carb rebuild kit
started and thermo but just want to be able to drive it and run threw the gears before I tear the head off
never really dealt with smog before.

 

UPDATE

Figured it out after rebuilding the original carb , fixing the stuck needle and float, resurfacing all the peices to remount and carb, still had a back fire so I checked my distributor was in time correctly with TDC. Then I pulled off the valve cover and low and behold someone had put a new double roller chain and missed the timing off by 2 teeth so I corrected that and while looking at the plugs I pulled a rookie mistake, 1-1 3-2 4-4 2-3 that was my issue.Should of doubled checked that first. But fixed a few others along the way
the truck runs great with the smog gone and egr along with the a/c. Smokes quite a bit so im guna drop the oil for the 4th time and refill and let it get to warm temp see if it goes away. If not I guess im doing a head gasket, fingers crossed its that and not a cracked cylinder wall.

 

You're doing fine, keep at it.