How long to machine engine?

Generally, a time of 4-8 weeks I would consider "normal". Some shops send out things like align boring/honing, crank work, etc, and each "sub" there will always be some wait. Then the inevitable "need to check for pushrod length and order them, etc. If you were thinking dropping it off, and saying "I'm in no rush" was OK, think again. You should be going in, giving them 1/2 of the estimate up front, and getting a delivery date. Things happen, so that may not be the bible truth, but it's the best you can get. Dont call..Stop down..I like once a week..And be ready to pay in full when its done. If you dont have the $$ for the estimate, you wont have it for the "might as wells" that will come up. I've found it's a 2 way street. If they do get things done, you need to be ready to pay. I've seen at least 5-6 engines a year go thru the shop..I gottta have it ASAP..then it gets done, and the guy says.."I'll gave the rest in 2 weeks." The shop I use now will not begin any machine work beyond /disassembly inspection, until a 50% deposit is given. Not that money is an issue in your case, just pointing out that it sometimes can be. I would start dropping in, randomly, and often.