I have taken a 5.9 out of a 99 durango with 78000 miles and replace my 5.9 in my95 ram with 243000 miles on it. it sounded like a good idea at the time. I used my intake and all my electical( as the computor change from ob1 to ob2) except I used the 99 distribitor but used my cam shaft sensor and left the plugs and wires on from the 99( thinking that it should work)everything was rehooked up the same as before. Once I drove it it was running and idling great but once it warmed up is started pinging really bad so I put in my spark plugs from the 95 and I ran alot better but it still pings when i acellerate. i have tried using premium gas and it made little to no difference. my question are what determines the spark plugs the engine compression or the ignition system? and also any Ideas what can be done to get rid of the pinging? Any help will be great