what motor oil should i use for the summer and for the winter?

 

You own an n/a fc I assume? I would recommend Vallvoline VR-1 Racing 20w50 in the summer and a good grade 10w30 on the winter for street driving. That's what I used in my R1 when I lived in Jersey.

 

^yup

If you only want to use 1 weight though, stick w/ 20w50 over 10w30

 

thanks

 

That's good advice. I'm still on my 10w30 'winter' oil. Gotta do an oil change soon.

 

Mazda only recomends 10w-30 for normal conditions, even for the HOTTEST climates - and recomends 5w-20 for Very Cold climates (AVG. temp below freezing), I would only recomend 20w-50 for the track or for an older well worn engine. I run 10w-30Castrol GTX and get 30+psi oil pressure at idle rising to 125+psi oil pressure above 3.5k rpm even on HOT days.