When are you switching to synthetic?

[AC sports]

New engine. Running in on mineral oil atm.
When are most of you guys switching to synthetic? I usually do it after 500 mls or so but noticed lots of people waiting til 5000+ mls?

[ClassAct]

New engine. Running in on mineral oil atm.
When are most of you guys switching to synthetic? I usually do it after 500 mls or so but noticed lots of people waiting til 5000+ mls?

10, maybe 15 miles at the most. If the rings aren't seated by then you've done something wrong. I think I drove my junk to town once after the cam was broken in and then went to synthetic.thats right at 10 miles, and I only did that because the break in oil was mother freaking expensive.

[1972ho]

If you got to some of the oil companies website they are saying you can to synthetic even during break in.They claim that it is myth about using regular mineral oils to break in rings.Check some of them out.

[4vpc]

If you got to some of the oil companies website they are saying you can to synthetic even during break in.They claim that it is myth about using regular mineral oils to break in rings.Check some of them out.

Mobil say this, but I think they must be referring to a new car, not a new engine.

[MadBill]

If you got to some of the oil companies website they are saying you can to synthetic even during break in.They claim that it is myth about using regular mineral oils to break in rings.Check some of them out.

Surely not the ones that sell break in oil?

[treyrags]

10 or 12 Wot's or dyno pulls, drain and fill.

[82c10step]

I have seen many event winning and record holding engines broken in with synthetic oil. Doesn't seem to be a problem.

[treyrags]

I have seen many event winning and record holding engines broken in with synthetic oil. Doesn't seem to be a problem.

I agree. I'm just too cheap to do the short initial change using the synthetic

[David Redszus]

How does one know when an engine is broken in?

Do we mean rings?: cams? gears? bearings?

[treyrags]

How does one know when an engine is broken in?

Do we mean rings?: cams? gears? bearings?

IMO there is no "break in" mechanically. As long as nothing is eating on itself it should be as good as it's ever going to get right off the bat. As far as ring seal goes I like to go by the look of the exhaust ports and headers. Preferably dry and gray.

[makin chips]

If you got to some of the oil companies website they are saying you can to synthetic even during break in.They claim that it is myth about using regular mineral oils to break in rings.Check some of them out.

Mobil say this, but I think they must be referring to a new car, not a new engine.

Do new cars not come with new engines? Lol.

Many car manufacturers use synthetic oil for the initial fill of the engine, AFAIK. I don't know of any that run every engine on non-synthetic oil before filling with synthetic. It's synthetic from the very beginning and they don't have huge numbers of failed engines due exclusively to the type of oil used. Every Corvette built gets synthetic oil and they seem to handle it just fine. Even the ZR1's. Why would any other engine be any different?

[Roundybout]

The only time I use a conventional oil is on a new/rebuilt engine with a flat tappet cam that could use the added ZZDP of a break in oil. After 500 miles or a few Dyno pulls it gets a synthetic. I'm partial to Mobil 1 0w-30w in street driven stuff.

[427dart]

I just stick with VR-1 non synthetic and change it every 6 months with the few miles per year I rack up on the weekend hot rod.
Oil stays clean on this engine with a good PCV setup. Running strong after 9 years now.

[Schurkey]

If you're using the thick, Moly-based paste on flat-tappet cam lobes and lifter bottoms, the oil filter can plug in twenty minutes of run-time. You'd surely want to change the filter...but I don't change oil. I just top-off as needed.

"I" have no patience for short-time oil changes. I install an asswipe oil filter on any "fresh" engine I fire up. The bypass oil filter keeps the oil "clean as new" during the break-in process. Some engines keep the bypass filter permanently, some engines I remove the bypass filter after a few hundred miles.

Amsoil sells the bypass filter kit new, as does Frantz. Not "horribly" expensive, especially if you consider them a "tool" and just move it from engine to engine as they go through the break-in process. On my own "new" engines, I've been filling with Synthetic oil, letting the bypass filter and the full-flow filter remove the contaminants, and change oil after thousands of miles. The OEM full-flow filter gets changed at oil change time, the bypass filter element gets changed when the bypass housing isn't getting hot any more, (Filter element is plugged) which takes...forever.

I get Frantz filters used off of eBay. I have a handful of them. Two installed permanently, on vehicles, one on my solvent tank, a couple "on the shelf".

Which reminds me...I need to get some fresh O-rings for a couple of them.

[cjperformance]

All the break in talk on this site is difficult to follow. I thought I remember some folks saying they install piston and ring packs dry or near so, and now its all cool to just go full syn oil. And one expert here says there is no such thing as break in mechanically. So I guess he means there is no wear any place in the engine during break in. Wow! I'll just stick to my,,, had to pull out the calculator to figure this out,,,methods I've used for 56 years.

its not cool to use a calculator anymore, you need to ask google!