You'll note the picture in my signature shows my car equipped with slapper bars.... and both front tires in the air.
Best 60ft is 1.43 seconds. (launching on the bottle) It bogs to consistent mid 1.6's off the bottle. The 1.4 60fts on the bottle do require a well prepped track. Otherwise, nitroused launches are in the mid 1.5's.
I'm not saying slapper bars are the ONLY way to go, but can be quite effective.