I just put Caltrac's on this year I've been to the track twice. My car is launching about like yours.The car starts to pick up the front end then it drops. My best 60' was a 1.46. Best ever was a 1.50 with SS springs. I didn't realize but yesterday going over the car I noticed my shocks were set on 6. I thought they were on 9. I don't know whether to loosen or increase the shock setting. But we both need to get the front up and hold it until we get off the line a few feet. I pitted next to my buddy in his mustang at the last race. He was getting consistent 1.39 60ft times with the front end 3 ft in the air running 10.60 et's.
I think it is all about getting the front end over the center of gravity just like pulling a wheely on a bike. When you do this all the cars weight is on the rear wheels and you will get the best traction.
I was told by someone with extensive testing to leave a .070 air gap on each side of the Caltracs. This has worked good for me but I think the fine tunning is in the shock settings and front end travel. Each time I lowered the front end the front tires pulled higher off the line and the 60ft went down. The only problem now is that I can only lower the front about and inch more. I may have to lower the rear but I really don't want to go that route.
Good luck