a small bottle of STP will do fine

the red bottle for 4 cyls has more than the blue on the ZDDP

lucas/hughes/comp/GM break in additives will work.

I just use a blue bottle of STP in my 440 with a 10/30 napa house brand oil change.

I use a napa gold filter on all of mine

my roller cam in the SB gets a bottle of STP and the 10/30 oil also,cant hurt to run I geuss..but I did go roller for this reason,and its now in the 2nd engine with different roller lifters this time.

no need for to much snake oil additives,i think some of the gas tretment might help carbon up the valves like mine were

I am cheap and use the STP from walmart for 2.00$ a bottle