[zoomzoomers]

Originally Posted by mrtodd

^This.

All the Honda engines I rebuilt I used dino oil to begin with, then switched over to synthetic after so many miles. My last engine I built, which also happens to be my current engine in my EH2, I actually used basic non-detergent oil for the first 2 changes, then regular castrol dino oil, THEN finally synthetic. I beat the shit out of the engine for the first 50 miles.

My compression on this engine is the highest I've ever had on all my builds. This isn't only my experience, but many other Honda builders have proven the same results. These aren't old engine builder tales. The science is simple - synthetic is literally too slippery for rings to seat properly. Rings need friction to seat, which is the reason why cylinders are honed at a specific grit.

Now, a new car will be different. The manufacturer WILL have done a short factory break-in/bed-in procedure before the engine is even installed in the chassis. This may or may not be enough to have the rings fully seated.

Do what you want, either way it's not going to make or break your FR-S/BRZ. But for those of us that are OCD builders.....we know what we're going to do.

I'm not oil expert. I mean all I do is drive it like I stole it. But my previous several Bimmers came with synethetic and didn't even have an oil stick. I know, you should have seen the BMW forums then when BMW of America released that info about the no oil stick. Till this day, I haven't heard many issues with break in or rings not seating properly. Now, blown engines is another issue LOL

On another note and I'm just curious here, but who in the world keeps their cars over 4 to 5 years max these days. So why worry so much? Plus these motors are well engineered these days and I hardly hear of anyone having issues due to improper break in.