this is really my buddys truck we have been trying to figure this out for some time now with no good out comes..
seems to run fine when sitting but as soon as you put it into gear it starts popping like crazy...

we have replaced
distributor (MSD including cap rotor wires)
upper lower intake set
spider injectors
had it timed at a shop (he dont know what it is eather)
changing plugs today even though they are new but never know

any help would be great guys and thanks

 

cracked or leaking exhaust manifold could cause this, is there a check engine light on?

 

yes i keep saying misfire but i can rem where at the moment