MakerBot Print is our newest print-prepration software, which supports native CAD files and STL assemblies,
allows you to interact with all your printers via the Cloud, and many other exciting new features.
You have the valves backwards. Your exhaust valve is larger than your intake valve, intake valve should be the large one. All the valve seats seem to be switched in the head. Still an amazing model and I'm having a ton of fun printing it, just threw me for a loop when I realized my printed exhaust valves were larger.