it don't sound like the gaskets, S19243H. your valves should be ok, sounds like you have a timing problem to me. if you move the dist. to you get the highest vac. reading and then move it back 2 ins. of vac. then that should be your best timing. if you have anything other than around 10 degrees at 900 -1000 rpm then the mark is wrong on the HB, but that should be your base timing. plug the vac. adv. off while you do this. you will need to adj. your rpm with the timing change. sounds like to me after you set you timing with the vac. gauge you didn't idle the carb. back down, or up which ever one was needed. as far as the conv. goes looks like the cam people would have told if you need a stall conv. but if you get the timing right i think that will work itself out. do the vac, deal and lock the dist. down, plug the vac. adv. back up and adj. the rpm's and carb. air screws as best you can get them and see that you have.