Year round street/track oil

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999
Location
CO
Does anyone have any suggestions on a good year round oil weight for street and track use? Im in CO and see temps in the summer near 105F and in winter have seen -18 a few times over the past 3 years. Id like to just stay with one oil. Application is a stock Renesis rotary. Car is expected to be tracked once a month year round at least. Not really looking for brand, weight only really. Thanks
 

Nederlander75

Thread starter
Messages
999
Location
CO
Id thought about that but was concerned about the VIIs needed for that spread. That aside it does fit the need though.
 
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8,051
Location
Michigan
For a Wankel? I thought that running synthetics in a Wankel engine was emphatically NOT recommended. 10w30 or 15w40 conventional oils I think would be your only options. Even then, I'm not sure if you can find an oil that will work year-round. A 10wXX oil is only recommended for used down to 0F by API's general guidelines. So then it would seem a 5w30 conventional would be the way to go, but I worry about the possibility of the extra VII's gumming up the apex seals over time. What does Mazda recommend?
 
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28,123
Location
Regina, Saskatchewan, Canada
Originally Posted By: A_Harman
For a Wankel? I thought that running synthetics in a Wankel engine was emphatically NOT recommended.
For what it's worth, there is at least one brand of synthetic out there specifically for Mazda rotaries, although not, of course, marketed or endorsed by Mazda themselves. I can't think of the name right now, but I'm sure a Google search would turn something up. If I recall correctly, the Mazda 787B did run some sort of synthetic oil.
 
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13,613
Location
Frisco, TX
Motul 300V is available in several weights (0w20, 5w30, 5w40, 10w40, 15w50) and is totally streetable. I have been using it for a year now and my UOAs show it can handle track days just fine. In fact, I ran the 5w40 last winter when it was below zero many times...even took it ice racing. :-)
 
Last edited:
Messages
28,123
Location
Regina, Saskatchewan, Canada
Originally Posted By: CATERHAM
Idemitsu makes a full syn' POE/PAO 10W-30 specifically for rotary engined Mazdas that would be suitable. Check it out:
Oh, sheesh, I think that's the one I was thinking of. I don't know how Idemitsu slipped my mind.
 
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10,146
Location
Burlington, Ontario, Canada
Originally Posted By: dparm
But how is their 10w30 any different from other group IV/V oils?
No idea, but any oil that's formulated specifically for rotary engines regardless of it's chemistry would be something I'd definitely look into if I had rotary engined car. I'm sure it's expensive, likely more than RL but less than Motul 300V. BTW, a 164 VI in a so called 10W-30 grade has got to be a record although I'm sure the HTHSV is also very high, likely more typical of a 40wt oil.
 

Nederlander75

Thread starter
Messages
999
Location
CO
Thanks guys. Ive also considered Idemitsu and can get it for about 1.50 less/qrt than Redline. In the US Mazda recommends only 5w20. However, in EU its 5w30 and in AU its all over from I think 0w20 to 20w50 depending on tempuratures.
 
Messages
10,146
Location
Burlington, Ontario, Canada
If it's cheaper than RL as Nederlander75 mentioned, it might be an option in place RL 5W-30 as it has a slightly higher 164 VI and I'm sure also contains no VIIs. It would be nice to get some more detailed spec's on this oil including HTHSV.
 
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