tuning is always good to have but when i used to run the spray before i knew a tuner id just retard the dizzy a couple degrees say 1.5-2 degrees per every 75 hp or so. keeps from cracking the ring lands if pistons are forged then retard 1-1.5 degree for every 75hp shot to keep the heat down in the combustion chamber. 100 shots not that big a deal without tuning just keep an eye on your plugs for any shiny specks and if you see this back timing down another .5 degree cause that would be excessive heating. never lost one yet and ive sprayed this old junkyard motor in a hulled out 92 hatch for years with a home made 2 stage one throttle activated zex 50 shot and a NX 75 shot or so on a button to hit when traction was available after 2nd gear so i think thats 125 shot after second gear all together! friends still running this combination with same 2 kits 4 years now netting 7:40's in the 1/8 mile here. and remember the higher you bottle pressure the harder the hit just dont go over 1100-1200 or your solenoids could start to stick open! just really an old war story i guess but good luck with her!