get a 160 and use throttle management. don't go full throttle down line and pull up elevator, use it sensibly. i mean you don't need to fly your whole flight at 3/4 throttle. 120 will be ok to but 160 will definately give that extra bit your looking for. and i fiberglass the insides of my firewalls now anyway before i even start building my plane....just in case...and it only takes like 15 minutes and 5 bucks or so.