You might remember me posting about bad idle on my 36" WB. Turns out the intake valve seat was on its way out...literally. Doesn't look like any permanent fix, I have it 'pinged' in place temporarly, but the engine is going to be replaced. its a kaw. 420v, how bigger can I go, hp. wise? its a 12.5, whats the biggest long block that will bolt in place? 17? 19? Not looking for any modding to make it work, just a long block swap. Thanks for your replies.