Shout out to Blue Print Engines.
A few months ago I bought a used BPE 347 that the previous owner said ran good. When I got it installed it had horrendous blow by, so I pulled it out and tore it down. I posted about this on a Facebook group for Blue Print Engine owners. When the Vice President of BPE saw my post, he offered me an excellent deal on one of their new 4 bolt main blocks, but my machinist found my block to be good, so I declined. I did have one broken piston ring land causing the blow by. When the VP heard about that he graciously offered to send me a set of the new forged pistons that they now use. Turns out that the older engines like mine used cast pistons that were prone to this type of failure. I of course said yes to the offer and today I received new pistons and rings at no charge! Wow what great customer service! I am not even the original buyer of this engine, they knew that and stood behind their product! I am now a loyal customer to BPE on all future projects.