I use playground chalk, on the WB wheel, mustly because the chalk comes in different colors, so we can tell which marks on the track are ours. I'll add more front-end weight when we get 2 or more chalk marks, the 1'st one comes at the hit when the slick squats.
I don't use a wheelie bar sensor, but Alan at A-1 Trans and converters suggested I try one when I asked about how I could reduce the "J" hooks I see on the driveshaft curve on my RacePak. He said it would tell me how much pressure is being put on the WB, and that would give me an idea how much more ballast for the front end. It's all about car balance, I can't tell you how many times I've told racers to put another 15-20 lbs on the nose and run a quicker ET, besides being able to steer the car.
I use the V300 RacePak data-logger, if you don't run a mag they sell a cheaper "Sportsman" model, but I run a MSD 20amp Mag so I need the V300. I know Bruce[ dreracecar] does not need a data-logger because he has figured out his 7.0 combo, but I'm trying to run in the 6's in Heritage JrFuel. So my "squigly lines" tell me what converter to run, what tire pressure, launch rpm, driveshaft/tire speed, shift rpm, finish-line rpm, besides fuel pressure, fuel flow, egt's, vacuum. Besides the RacePak, I also keep track on my run sheets of weather, jets, timing, ET slip, driveshaft speed, exhaust at the hit, max G's, egt, fuel pressure & fuel flow at shift and at finishline, rpm right after the shift [ true converter stall ] oil pressure, high speed shim pack, and track, tire, engine, temps, at startline and after the runs. I keep a run sheet for each race, so I can go back to the sheets the next time I race at that track.
I hope this helps.
Feel free to call with any questions, 805-444-4489, Jon at Hayden Wheels and JrFuel DragsterAssociation