We have been in the wheelie bar business for nearly thirty years now and we have them pretty much sorted out.
Standard 60" bars will run most four link cars down to the low 8's without any problems.
Ladder bar cars cannot run non spring loaded bars in their traditional sense. Ladder bar cars have too much rearend rotation, and drive the tires too hard to use a standard bar. Likewise, long wheelie bars do not lend themselves to ladder bar cars either. Ideally you want a 50-60" spring loaded bar for a ladder bar car. (NOTE: there always some exceptions to the rule, but this is true in most cases.
Top Sportsman bars are necessary for chassis tuning once you get down into the lower 7's. These bars need to be longer and stronger to control leaving off of them. Where slower cars use the bars to control the wheel stand, the faster cars use them as part of the launch. We tailor each set to your specific power plant so we can best match your set up. We vary the upper tube sizes, and tie bar arrangements to make the bars flex the right amount for your launch.
Pro Mod bars are for the truly overly powerful race cars. These are the only bars we tie all the way around. We build these custom to each car after speaking at length with the tuners of each car.