Oil burning on my recently buil 302

[The blk67]

Hi guys, I am having an oil burning issue with a recent rebuild in my car.
302, gt40 3 bar heads, 5 angle valve job, x303 cam, 1.6 roller rockers,
Gt40 tubular intake, with 1inch spacer and rebuilt stockbottom end.
As engine idles, there's no signs of blue smoke, the moment I start to drive it will smoke as I up shif, once cruising it stops the blue smoke, as I deceleration or gear down blue smoke, I need some help with this issue

 

[AeroCoupe]

Did the machine show home the cylinders correctly? I had this happen once and had to tear the motor back down and the cylinders were not finished honed. Could also be a poor ring selection or installation. Best way to tell this is to do a leak down test.

 

[Blackhawkxx]

Valve seals will also act like this. If they were replaced there is still a slight chance that one or more was damaged with the install.

 

[Noobz347]

How many miles are on these heads?
Were they also rebuilt?

It sounds to me like no matter what it is, you're going to have to pull the intake and heads and explore until you find the issue.

I saw that somebody already suggested a leak-down test. That's a good place to start.