500 miles on new build. Cool to switch to synthetic? Or naw
 

Got 500 miles under the belt of my rebuilt engine. '95 block, 84mm JE pistons, B6T rods, BP4W head, in a fwd Mazda Protege. Been running pennzoil yellow bottle after 100 miles on rotella 30w. Been NA since first start, I didnt have all my turbo goods lined up and wanted to break in NA with a full exhaust so everything was quiet on first start up and I could hear the engine good.

Initial FM break-in followed. No surprises, running great. Pulling ~20in. vacuum at idle.

So, getting ready to swap on some kitty-power and I want to switch to synthetic. When did you switch to synth on your rebuilt engine?

I've read "wait until X miles, wait until this or that.. or do it now, oe cars come from the factory on synth" I understand that last viewpoint, but curious what you guys think on the subject.

Once the rings are seated, which if that doesn't happen in the first few min of operation.....they will never seat....there is no reason to not treat the motor exactly how you expect it to be treated for it's entire life.

I will make a few pulls from 2500 to about 5000 rpm, snap the throttle closed and let it coast back down. You do that 3 or 4 times and the rings are seated.

Change the oil at that point (literally like 10 min of run time) and put what ever oil you are going to run in it, strap it to the dyno and make full power pulls.

This pull was with about 20 min total run time on a brand new motor, was to I think 8300 or 8400 RPM and 25+ PSI.

You didn't mention what rings?

What does your ring manufacture recommend for the bore surface finish used?

That is what I did, minus the directly after oil change. First start up - no leaks - warm up - seat rings procedure. I changed from rotella 30w at 100 miles, to Pennzoil 10w30, changing it at 200, 300, and now, 500 miles. Wix oil filter each time.

The ring seat and break-in aren't things I think I'm too concerned with now at this stage. The car hasnt been grandma'd around too much and has seen some WOT, redline and lots of engine braking. No highway. Its going well, cut open oil filters look unalarming. Oil pressure is always tits (BE pump +1 shim)

I feel its ready to turbo, I know I am.. but wondering on what the thoughts are here at going synthetic now at this mileage. Does it even really matter by now?




They are JE rings. Bottom end was machined/assembled at a local shop, a very long time ago. 5 years I think. Then sat sealed up in the garage lol. Shes going now though!

You could have gone synthetic right after you seated the rings.
I use Lucas Oils "Break In" oil for startup and ring seating then immediately go to Valvoline VR-1

I wait 3-4 race hours or 1000 street miles out of an abundance of caution. The vast majority of the break-in happens on the first few pulls, but the moment you put synthetics in the motor, there's no more "break-in" happening, at least when it comes to the rings. I use Joe Gibbs BR 15w50 for the first weekend or two of racing and monitor oil consumption very closely. Once it stops burning oil, break-in is done and you can switch.

Why do you use Joe Gibbs BR break in oil over Amsoil? Mostly just curious. I have been using Amsoil break in oil recently, but that is more to do I just pick it up locally when i restock up on trans and diff fluid.

Thanks. I may just put 1000 on it for good measure and go from there.

I did the 500 mile break in changed oil 3 times @ 15miles, 100 miles and 500 miles. I didnt switch to synthetic until 1000 miles. Used Dino Rotella on the first 1000 miles.

I called Amsoil a few years back and talked to a tech guy there and he said they recommend 1,000 miles before switching.