I just started up my new 460 after many late nights of swapping it over after work and it ran great! BUT... white smoke. At first I wasn't concerned, I expected some smoke after handling all those parts and burning off paint, etc. But when the white smoke didn't quit after a little while, I shut it down. I stopped a couple of times to check the oil to make sure there was no water in it and it is fine. There is water dripping out of the tailpipe but I expected a little of that as well because my old engine blew a head gasket (I confirmed it with a compression test & water in the oil) and I thought there might still be some coolant in the exhaust system.

So, is it time to panic? Did I do something wrong? Is it safe to run it to see if it clears up? I was VERY careful when I installed the intake manifold because I've read about it being tricky.

 

I'd run it and keep a close eye on the temp gauge. Could be a lot of coolant in your exhaust.

 

what's a little while? how long did you run it?

I'd give it at least 10 minutes to warm up, assuming it's not billowing white smoke/steam. Longer if it's cold out.

It should at least start diminishing at that point. If not - I'd do a compression test on all cylinders.