"And, don't forget the roundy-round boys preload with the springs all the time. No reason it can't be done in a straight line."
I'll try not to rant here...roundy-round cars are night and day different. They ask for a completely different dynamic action than drag cars because it's a straight line. We want launch control and firm handling down the track. Pre-loading springs for control causes ill handling at speeds and braking. The ONLY exception being shocks as they're dampers. They can be made to dampen the same in one direction and different in the other if they're double adjustables. Pre-load by virtue of the bar adds work force when needed (launch) and control when needed (down track and braking) without unwanted forces after launch.
...Look into the deal Dave says about lighter springs and "stored energy". Consider everything we've been discussing, and if possible have someone knowledgable watch your car launch and take notes. Remember, longer on the drivers side (lower ladder bar adjuster) adds static wt on the pass side. The opposite is also true. Don't cloud the issue with "instant centers". The instant center is the forward mount. The bars are the levers. The levers plant the tires and when right will not allow the car to sag at all on launch. in fact the top of the tire should be nearly visable on launch depending on how low the car sits. It also sounds like they're in the right position to get the lengthening force I was talking about earlier.
Billy...I don't disagree on G forces, maybe you're even a little low. And I came up with roughly 140HP in my sled example based on observed times/speeds. So we're there.
...lookin forward to hearin how the car's doin. You never said what it was, did you?