Strange, a plane designed for 80cc engines, and anything installed greater than a 50 requires firewall modification? Lanier Arfs are usually pretty tough, and heavy as noted...but at this size, even if it comes out at the advertised 21-22lbs...anything up to and including a DA or 3W85 should be good (or DL85...come on Bob!!!!). I cannot imagine the DL50 doing much justice in this plane, unless it is for very general buzzing around, like the G62 in a H9 33%er. I have two DL50s and I love them, but I just wouldn't consider this to be a good match.