If it's not coming out at idle and all RPM's then your fine, if it is, it's most likely a head gasket, which there is a tester out there to use so you don't have to go down to the local mechanic and get ripped.
I finally saw a video of my 12.20 pass and when I hit 2nd a small small amount of white smoke shot out shifting at 5600, my car ran strong, no leaks and when I pulled the motor out recently everything was still perfect. Ok, well the valve train was a little loose but other than that nothing out of place, no extra wear.
If you are adding oil every so many miles then yeah, maybe valve guides, had that happen to me on mustang #6. Summit rebuild kits are cheap and you can replace everything to the piston rings.
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