what weight/kind of oil in a rebuilt engine?

[aalugo2000]

hey guys,
my car is in the shop right now getting new pistons (020 overbore), rods, valves, oil pump, and all the gaskets. prior to this i have always used mobil 1 10w30, and now i was wonderind if i should change weights or brands after the rebuild. im also running a cam and planning on raising the rev limiter to about 6500, and im also spraying. feedback is appreciated [img]smile.gif[/img]

[98Camaro3.8]

I would stick with Mobil 1 10w30, but run a conventional (ie, non-synthetic) oil for the first few changes.

[malice10985]

Originally posted by aalugo2000:
hey guys,
my car is in the shop right now getting new pistons (020 overbore), rods, valves, oil pump, and all the gaskets. prior to this i have always used mobil 1 10w30, and now i was wonderind if i should change weights or brands after the rebuild. im also running a cam and planning on raising the rev limiter to about 6500, and im also spraying. feedback is appreciated [img]smile.gif[/img]

I am doing the EXACT same thing this weekend. I am going to use really cheap oil until the piston rings seat and oil consumption stabilizes. Then I will resume using precious, precious, Mobil 1.

['94firebirdv6]

Use Mobil 1 supersyn oil 5w30...they're website says that you do not have to run conventional oil first on a new engine/rebuild that you can run their synthetic the first time

[Dominic]

Mobil1 is good oil, however their 30 is a little on the thin side. With Mobil I prefer the 0W40 european car formula, it works well in a 3800-II.

[Die Ford V8]

would it be bad to run castrol 10W40 on my engine instead of 10W30. I was thinking since I have almost 140,000 miles on her that thicker oil would be better. tell me if im wrong thanks

[aalugo2000]

thanks for the feedback... afew different opinions [img]graemlins/popcorn.gif[/img]

can anyone give me the reasons as to why you would not start right off with the synthetic after a rebuild?