Another oil question

[70 RAG TOP]

I ve read somewhere in this forum that you should not use synthetic oil in a newly rebuilt engine until it has about 6000 miles on it.  I am at 500 miles and I am going to drain out the break in oil( comp cams 10w30 break in oil) and put in fresh oil and filter.  I had decided to go with the Brad Penn oil until I saw that it was a "synthetic blend".
My question is: is syn blend ok to use or does it need to be straight conventional oil?

Thanks

[oldkimmer]

..........I would run the dino oil this time then switch over.........mosty syn blend is only about 10-20% anywayus.........kim....

[Chryco Psycho]

I agree run a non syn but with high zddp or additive to keep the cam alive

[70 RAG TOP]

Can you  give me some suggestions of a good conventional oil with high zinc/phos.

Thanks
Mike

[Chryco Psycho]

I would just get Castrol 10-40 & add Cam Saver or Comp cams additive

[70 RAG TOP]

Thanks, I'll go with the Castrol and the additive.

[72cudamaan]

If you're sure the rings are seated ( if honed properly they are) then you could go ahead
and use synthetic oil. The only reason to not use synthetic is so that the rings will sufficiently
scuff on the cylinder walls and seat.

[70 RAG TOP]

Is 500 miles usually enough enough to break in engine or should I keep the comp cams break in oil in a little longer?  I assume the machine shop honed the cylinders properly but can't be sure.
Thanks

[Chryco Psycho]

I would run it longer with non synthetic , once the synthetic is in there you cannot go back to non syn & seat the rings in further

[72cudamaan]

I would run it longer with non synthetic , once the synthetic is in there you cannot go back to non syn & seat the rings in further

If you don't know what kind of equipment was used to finish the cylinders then you may as
well wait until your first maintenance oil change. Neil is right, you can't go back to traditional oil and
potentially fix an oil consumption problem. I know that with the equipment I was using, by the time you had rotated
 the engine enough to install pistons and adjust the lifters, the rings were seated.