ken-x8

You can run a car without ever changing the oil for that long without seeing problems.

The letter Ramart posted is interesting. There are at least two other letters like that circulating, with the same picture. They're somewhere on this site, in oil or synthetic oil threads.

Ken

gwilliams6

Good post. Back when I raced my modified RX7 in the late seventies and early eighties I used Amsoil in my 400HP turbo 13b engine (that was built by Racing Beat) and it worked great.

A key point mentioned here in this linked article is the risk in switching to synthetic after your engine has years of mineral oil use. So they seem to recommend Royal Purple if you use it from the beginning (after break in with mineral oil).

Any good quality oil of the right viscosity will be fine, but be aware that some Mazda dealers have denied warranty engine replacement after an engine was found to have been run on synthetic oil. This has been argued and debated and challenged, and yet some RX8 owners were denied engine replacement under this situation. (even though Mazda recommends synthetic in other foreign markets)

I personally have used synthetics in my past RXs but choose to stick with Castrol Mineral oil for my 2008 40th Anniversary RX8 while under the 8yr/100,000 mile rotary engine warranty. It's your choice, your engine, your warranty.

Waylon Chen

So do you have to use a funnel when changing oil? And a long one? What is the point of it?

hoss -05

iTrader: (4)

To keep oil from draining back into the intake. Check out the nipple at the top of the oil fill, that nipple dose not drain back into the pan.

Waylon Chen

So short funnel will do? Or should I get a long extend one?

RIWWP

iTrader: (2)

A funnel is just to prevent spills. Get an appropriate funnel and don't over-think it. It's not really complicated

ken-x8

Short funnel or a steady hand. Wrap a rag around the filler neck if you don't have a funnel and aren't sure if you have a steady hand.

I do without a funnel. When I was a kid I learned to ride a bike without training wheels, and the confidence never left me.

Don't use the same funnel for different fluids. I once saw a guy at a gas station use the auto transmission funnel when adding engine oil. Not only did his "ape hanger" stance look ridiculous, but the next guy to top off his ATF was going to have it contaminated with engine oil.

Ken

badinfluence

+1 to the Balancing Zinc and Detergent debate. Does anyone have a spec sheet with a list of oils and their Zinc & Detergent content?

Iluvrevs

For mainstream oils check pqia.

Sato Tatsuya

Has one of you guys had experience using Motul 0W40 oil before? Is it good, or is Mobil1 better??

BigCajun

iTrader: (1)

You are asking for a definitive answer to a question that is highly debatable.
Any answers you get will be matters of opinion.
The one thing most agree on is that frequent oil changes (every 3k miles) are more important than oil type.

Sato Tatsuya

Thank you! I knew that, I was just wondering if anyone had any experience using Motul 0W40, but then after reading what you just wrote it made sense that what I asked is a redundant question...LOL! Thank you!

pistonhater

My 2008 manual says the exact same thing as your 2011.

77mjd

Got some info from a guy that has torn down and rebuilt many rotaries in his day. He swears on using Valvoline VR-1 racing oil in 10w-30 non-synthetic. I don't remember exactly how it was explained to me but it had something to do with this oil having a higher zinc content.

Xeridae

In your opinion, do you think the SOHN adapter is worth the money and effort or is there minimal benefit to be had from it?

RIWWP

iTrader: (2)

There is significant benefit with the SOHN. You go from injecting dirty 4-stroke oil that could clog the OMP lines and was never designed to be burnt to injecting clean 2-stroke that was designed to be burnt.

There is no downside.

Carbon8

iTrader: (4)

Nobody will claim minimal benefit, and if they do they should be banned from ever giving advice on a rotary.

Its common sense!

Inject clean oil or dirty oil?
Run synthetic in the case for test proven minimal bearing wear or not?

Xeridae

Thanks for the info. I read all of your posts about modifications but wasn't sure about this one in particular.

Waylon Chen

Hey I used full synthetic in January, can it be last till September? Mobile one filter, good stuffs!

Waylon Chen

Will synthetic double the oil change intervals on any cars?

paimon.soror

iTrader: (15)

Mileage? It wont last until april if you put 1000 miles on the car every other week since january

On any car? No

On some cars? Yes

On the RX8? No

Waylon Chen

I fill full gas about per 10 days, max per week, I think I ll go much less mileage than that, can it last through 9 monthes tho? That way I can change my oil in sep and mar which are warm lol

paimon.soror

iTrader: (15)

not sure you are getting my point. You want to change your oil every 3000 miles on the 8. Regardless if that is one day or one year.

Waylon Chen

Could be 6 month for me... But even with synthetics?

Carbon8

iTrader: (4)

Im still retentive enough to not run oil more than 3 months regardless of miles.

I do 2500 miles or 3 months whatever comes first, but at the same time thats only two oil changes a year for me.