Im quite surprised by these responses but im glad I posted the pic - I've gone to the same machine shop for probably 10-15 years and never had any issues at the track, but then again ive never tried doing a leak down test either with pressure or vacuum. I will this time around. Im going to be safe and just take the whole short block to a new shop and have it re balanced and honed per my new application. I did have a mysterious blue smoke issue at about 1000' down the track that was never determined, who knows could havwe been blow by this whole time! Any advice o what valiues are passable for a leak down test? I would like to test the assembled motor this time around... What are good vacuum numbers and over what duration of time?