Ideal oil for built 13b (rotary)

Aramir

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Aramir

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Which is why most builders will delete the oil metering system and run synthetic oil and premix 100:1
I understand the principal but you would need to tune for fuel injection on no acceleration else risk running the motor dry and as is this is a street car i dont think its worth going that route
 
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Aramir

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Here is a tech bulletin from Penrite dated 2010 https://penriteoil.com.au/assets/tech_pdfs/157 MAZDA ROTARY ENGINES AND SYNTHETICS UPDATED.pdf

In it it states that hpr10, a semi synthetic, can be used in rotaries. However, on their website documentation it states that hpr10 cannot be used in rotaries whereas their PAO synthetics do not have this warning but according to this bulletin they should lol.

The plot thickens..
Starting to feel like this argument goes in circles ad infinitum
 

SR5

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Here is a tech bulletin from Penrite dated 2010 https://penriteoil.com.au/assets/tech_pdfs/157 MAZDA ROTARY ENGINES AND SYNTHETICS UPDATED.pdf

In it it states that hpr10, a semi synthetic, can be used in rotaries. However, on their website documentation it states that hpr10 cannot be used in rotaries whereas their PAO synthetics do not have this warning but according to this bulletin they should lol.

The plot thickens..
Starting to feel like this argument goes in circles ad infinitum
Point-of-Order!

Lets stop using the word synthetic, as it's confusing, and instead start talking base oil Groups, as per the BITOG front page (written by Mola)

Group I - solvent refining - conventional
Group II - hydrocracking - conventional
Group III - severe Hydrocracking, Hydroisomerization and Hydrotreating - synthetic (by performance), but still from an oil well
Group III+ - Gas To Liquid GTL - synthetic (by production)
Group IV - PAO - synthetic (by production)
Group V - other e.g. Ester, AN alkylated napthalenes - synthetic (by production)

That Penrite document refers to HPR 5, HPR 10 etc, which Penrite call Full Synthetic, but they are Group III oils, which are effectively more highly processed Group II oils. So similar base chemistry with less impurities and better performance (oxidation stability, viscosity index VI, etc). Penrite say this is OK for rotary engines, and I tend to agree.

However Penrite believe that Mazda's reluctance to use synthetics is referring to full Group IV and Group V synthetic oils, or semisynthetic oils that are part Group IV and Group V, and I also tend to agree.

In particular Penrite say to not use their SIN oils in a rotary, their SIN oils were 100% PAO & Ester, and have now been replaced by 10-Tenths which are 100% PAO & Ester.

So taking this advice at face value, its says Yes to Group III oils (and by implication also Group II conventional), but No to Group IV & V oils (which would include Penrite 10-Tenths and Motul 300V-assuming it contains esters).
 
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Aramir

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Point-of-Order!

Lets stop using the word synthetic, as it's confusing, and instead start talking base oil Groups, as per the BITOG front page (written by Mola)

Group I - solvent refining - conventional
Group II - hydrocracking - conventional
Group III - severe Hydrocracking, Hydroisomerization and Hydrotreating - synthetic (by performance), but still from an oil well
Group III+ - Gas To Liquid GTL - synthetic (by production)
Group IV - PAO - synthetic (by production)
Group V - other e.g. Ester, AN alkylated napthalenes - synthetic (by production)

That Penrite document refers to HPR 5, HPR 10 etc, which Penrite call Full Synthetic, but they are Group III oils, which are effectively more highly processed Group II oils. So similar base chemistry with less impurities and better performance (oxidation stability, viscosity index VI, etc). Penrite say this is OK for rotary engines, and I tend to agree.

However Penrite believe that Mazda's reluctance to use synthetics is referring to full Group IV and Group V synthetic oils, or semisynthetic oils that are part Group IV and Group V, and I also tend to agree.

In particular Penrite say to not use their SIN oils in a rotary, their SIN oils were 100% PAO & Ester, and have now been replaced by 10-Tenths which are 100% PAO & Ester.

So taking this advice at face value, its says Yes to Group III oils (and by implication also Group II conventional), but No to Group IV & V oils (which would include Penrite 10-Tenths and Motul 300V-assuming it contains esters).
Thankyou for the clarification, my point being that on their current document for HPR10 (a group III oil, said to be okay according to that bulletin) has a warning against use in rotary motors. Whereas there is no such warning for their PAO 10 Tenths oil (said to be not okay in the bulletin).
Potentially an oversight from their marketing team? Who knows
Added to this, Mazda apparently sells a PAO based synthetic oil for the rx8 but only in japan (need a citation for this, its hard to find information on this oil) which would turn the table on the group III = good, group IV= bad argument.
 

SR5

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Thankyou for the clarification, my point being that on their current document for HPR10 (a group III oil, said to be okay according to that bulletin) has a warning against use in rotary motors. Whereas there is no such warning for their PAO 10 Tenths oil (said to be not okay in the bulletin).
Potentially an oversight from their marketing team? Who knows
Yeah they did say HPR10 for a rotary was ok ages ago, now they say no for HPR10. Maybe the formula has changed, maybe they learned more, maybe it confused too many people and they went back to what Mazda said.

I don't think chemistry, engineering and physics has changed much since 2010, but the number of people willing to reach for a lawyer when things don't go their way has significantly increased. The easiest defence for a small company is to point to a big company.

I still think a quality mineral (Group II) 20W50 is the way to go. But it's your car, so it's your choice.
 
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Hey guys have a question regarding the ideal oil for my built 13b.

Long story short i have a rebuilt 13b with a single turbo aiming for around 400whp. The tuner recommends i run a 15w-50 for good oil pressure and he was recommending motul 300v. Being that im in New Zealand, Penrite sells a similar product in their 10 Tenths range which is also a 100% pao esther blend and is about 40% cheaper so this is what i plan to run.

My main concern with this oil is that it has a flash point of 206 degrees compared to motuls 236 degrees and its antiwear package is around 1800ppm zddp.
Ideally i want an oil with low deposits and historically this has meant Mazda will only endorse full mineral oils, but with a build of this nature i feel like a full synthetic will offer better and more consistent protection.
My concern relates to whether the Penrite's relatively low flashpoint and high zddp content is likely to be an issue for deposit build up.
Also for what its worth i plan to premix and will be running mobils 2t full synthetic 2stroke.
Any insight or clarification on this matter would be greatly appreciated, thank you.

Back in the 80's I had a peripheral port 13b @ 309 HP. I ran Castrol 20/50 for over 75000 miles with no issues.

https://www.amazon.com/Castrol-03095-20W-50-Motor-Quart/dp/B00JGQLSH8?th=1
 
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