my 54 and running like crap!!

I set the timing but sounds like its missing at cruising speed like 35 40 mph. Is this what happens when the vac adv takes a*****? I dunno but shes gotta be running better then this for the DEADBOLT concert this weekend. Dont really know where to go from here??? Help, befor it get ugly and people get hurt.

 

54 what?

 

its a chevy

 

We got it running better now.

 

So, what was the issue?