[Bosk]

Hey all. I have a 92 K2500 with 350. Couple years ago i did a TBI to carb swap. Ran fine until couple weeks ago. Just put an RV cam in and first issue was , rocker studs began to push out. Going to swap heads for ones with threaded studs. It ran fine until the other morning. I started it and now its missing on #8. Ive swapped the cap , ( HEI ) , plugs and wires and still missing. Did compression test and was fine. Could it be the coil in the cap ? Maybe the hole in the head ? Im at a loss. Thanks in advance

 

[chasracer]

So you already checked #8 and it's not pulling a rocker stud?

 

[2old2fast]

Are the valves opening on 8 ?

 

[BogiesAnnex1]

Hey all. I have a 92 K2500 with 350. Couple years ago i did a TBI to carb swap. Ran fine until couple weeks ago. Just put an RV cam in and first issue was , rocker studs began to push out. Going to swap heads for ones with threaded studs. It ran fine until the other morning. I started it and now its missing on #8. Ive swapped the cap , ( HEI ) , plugs and wires and still missing. Did compression test and was fine. Could it be the coil in the cap ? Maybe the hole in the head ? Im at a loss. Thanks in advance

Knowing the exact cam spec’s would be helpful? Typically an RV cam is not so radical as to cause or result in rocker stud problems, but to that end the TBI heads don’t accommodate very much lift and that goes for piston to valve clearance. So the cam lift and rocker arm ratio gets to be significant pieces of info. Cam timing to crank also as a bit off can be a problem with pistons meeting valves.

Studs pulling are possibly this as above or the bottom of the spring retainer hitting the top of the valve guide.

Bogie