Break in miles and oil questions
 

So during rebuild/refresh I am replacing all rotor tips for Atkins 2 piece ones. Corners seals for solid Atkins ones and all of the seal springs. Reusing most side seals but will gap check and no doubt replace a few.
Will also be replacing front and rear stationary bearings but not centre or rotor bearings. So questions is what is the rule of thumb for break in miles and break in driving type. What lil is best to run. Usually. A mineral I believe but not sure on grade. What oil change program should I follow and what is best to swap to after run in is all done. Think I had a 10w40 semi from memory before.
I will have the engine running on wastegate pressure for boost initially which is around 8psi but guess I won't be spending much time there for the first few miles at least.
would like to hear the general view.
Thanks guys.

http://www.mazdamotorsports.com/pdfs.../97CatComp.pdf

I would follow mazdaspeed's break in procedure (page TT-22)

Thanks for the link.. some useful stuff there!

Okay so for my break in does a 10w30 or 5w30 mineral sound good and then a 10w40 fully synth after seem reasonable. I might do a 10w40 semi inbetween to give it a flush through?
Thoughts?

Cheers
Lee

Your weights seem a bit thin for a performance rotary ;)

I'm a big fan of both Rotella 15w40 and Valvoline VR1 20w50 oil for break-in and anyone choosing a non-synthetic oil, and Idemitsu full synthetic 20w50 after break-in (running the Idemitsu 10w30 in colder climates).

What ambient temperatures are you seeing where you live, both in the summer and winter? Up in NJ I ran and recommended 20w50 in hotter months and 10w30 in winter months for street driving.

Rotary Performance, one of the longest running rotary shops in the USA, recommends 20w50 year round in their Texas climates for performance-driven FDs.

Don't forget our engines have the rotor ring gear to stationary gear interface that leads to a constant shearing force on the oil, much harsher than a piston engine environment.

I run 20w-50 year round down here in GA, very common in warmer climates.

These are performance machines, almost always making in excess of 300whp. What was recommended in stock configuration is not always going to still apply.

Okay.. interesting... I would not have thought this heavy at all. So here in the UK ambient air temp winter I would say is average maybe 5°C where I am. Summer.. if we have a good one 25°C! It will be driven in summer mainly anyway. or from spring in the dry at least. So temps will range from around 15°C to 25°C.

Would love some feedback. A single synthetic I can use year round would be great. I will start break in hopefully in a few weeks with a mineral around 15-20°C odd days so handy to know thoughts here too. and is it worth getting a cheap semi sythn just to run it up and flush through the mineral oil out of the coolers and stuff before I put the full sythn in?
Cheers.

Just an additional thought here.. do I really need to run mineral oil for break in? Could I use a semi-synth? I have only replace 2 bearings and tips. Side seal and oil rings and going again. What is the reason behind using mineral oil. I really never stopped to think. is it because a synthetic is too efficient and therefore slows down the break in process?
Also what is the engine capacity for a 20B please?

Thanks in advance.