I have an enclosed trailer and a small class C motorhome so most of my stuff is already packed. I typically don't travel super far from home and most of my races are single day anymore, or I'd probably pack some more extra spare parts. I've also try and make my racing budget friendly so my cars are nothing special running mid 10's and slower in the 1/4 with basic combos that require little maintenance.

Air Tank
Enough race fuel for the weekend
fuel funnel
Toolbox with typical tools (wrench's, pliers, screw drives, sockets, ratchet, electrical tape, spark plug gapper)
Timing light
Atleast 1 qt of motor oil and trans fluid
Brake Cleaner
Bottle jack
Floor Jack
2 jack stands
Spare parts (rocker arms, pushrods, set of spark plugs, carb gaskets, jets, extra carb return spring, throttle cable, tire tube)
Spare trailer tire
Battery charger
Extension cord
Helmet, racing jacket and pants
tire gauge
Enough food + drink for the race day