The last one I can remember is the Allen Hartley Double Vision TAD in the 90’s. Had the Cavaleri brothers tuning. The combo might still be legal. I think they ran nitrous oxide but not positive.There have been a few guys that ran twin engine dragsters in competition years ago.
Are there currently any classes in NHRA where a twin engine car would be legal if someone wanted to build one?
I can't think of any classes that currently allow more than one engine, and definitely not TAD, that was written out of the rule book by early/mid '90s. In that same era, around '92, my dad built 2 647 cube Hemis on nitrous for Lou Patane who had a beautiful Frameworks car built for the double engine combo. It was a wild machine. I'll see if I can find a pic, or maybe someone has one they can post.The last one I can remember is the Allen Hartley Double Vision TAD in the 90’s. Had the Cavaleri brothers tuning. The combo might still be legal. I think they ran nitrous oxide but not positive.