Nick, please expand your reasoning for saying the 951 are "under engineered".
What's wrong with them and what should have been done to them?
i'm no 951 expert but here's what I do know... because i've been lectured on this subject once or thrice
quite simply, they are a doomed machine, the pistons are like coffee cans and the cases aren't strong enough to take a hit, so they rarely survive a failure without a crack or blowing a hole all together, its really not a question of IF a 951 will fail, but WHEN, and sadly when they do, its about a 60% chance that the cases will blow a hole making the rebuild $300 more expensive. Even if the top end locks up, the crank rods are still very likely to do serious damage to the 951 cases and crank. In contrast the 717/787 cases generally survive a top end failure or a crank failure, they do crack/ventilate on occasion, but not nearly as often.
from a rider's perspective the trade off is this, higher top speeds, and killer mid range power, meaning you can enjoy improved acceleration and higher speeds touching the low 60's vs mid to high 50's on the same ski powered by a 787. This is even more noticable on say a GTX vs a GSX, since the hull is so much bigger on the GTX.
You'll enjoy increased performance but the life of the engine WILL be shorter.
what should be done ? fog often, warm up the engine before you jam the throttle right out of the ramp (i'm talking to YOU dennis ! lol)
and if you can bear the expense or do the work yourself, tear down the engine every season or two depending on usage inspect the crank, cb shaft, top end, and if there is ANY doubt, replace questionable parts, and reassemble. I'd even go as far as suggesting that even if the crank appears good, sell it as a good used crank, buy a core crank, and replace the crank, and possibly do the same for the top end. this is much easier if you do your own work, what your trying to avoid is a complete blowout. if you have a blow, then you have to spend upwards to $300 shipped on cases (and this is becoming the entry price on 951 cases now, i know this from experience) then rebuild from there.
IMO a reman engine with a 2 year warranty is MUCH more critical if your running the 951 powerplant vs a 787, not really because one is more prone to failure but really because the failure is generally spectacular !
