slipstream444

Good post Spitfire -

to the OP (since you weren't able to figure it out from the info presented so far) - NO, 0W50 is not an appropriate weight for an S2000 that has no modifications to the oiling system to accommodate a higher viscosity oil. Use what you like - just take responsibility for the results.

Simplified: Oil has two main jobs in an engine - lubrication and cooling. Viscosity is a fluid's resistance to flow. The higher the viscosity - the higher the resistance to flow. Lower flow = higher temps. Higher temps = higher wear and reduced oil and engine life. If your S2000 sees 8000-9000 RPM, do you really want to limit the flow of oil to critical parts?

There are no conditions on earth under which an S2000 with a stock oiling system would ever require an oil viscosity higher than a 40 weight oil. The temps required to justify a 50 weight oil are well above the operating range capability of the S2000.
If you lived and operated your S2000 in the hottest desert on earth, you would run a 5W40 or 10W40.
Using anything thicker than a 10W30 in temperatures lower than 100-115F is simply a waste of fuel (the increased drag caused by running a higher viscosity oil) and decreases engine performance. There is simply NO benefit to using an oil viscosity higher than recommended by the manufacturer - this includes track use.

bgoetz

The purpose for using a higher viscosity oil in more aggressive driving is that it coats better (think of syrup on something vs. water) and thus lubricates better.

I actually noticed better gas mileage with the 5w-40 eneos than the 5w-30 Mobil 1.

OP, do not go with the 0w-50 it has too high of a viscosity at operating temps. IMO the 5w-40 is the perfect oil for the S2k, provides the best lubrication for spirited driving and track use if that is your thing, plus a lower cold start which IMO is pretty important unless you live in a climate that is above 50 F all of the time. Plus it is Eneos oil which IMO is one heck of an oil, I have not found anything better and I have tried all kinds.

Cheese and Onion

Lubrication Engineers 8130 10W-30?

TuRbo_S2000

Does anyone know how the Eneos compare to Amsoil?

slipstream444

Your assumptions regarding oil viscosity are incorrect.
"Coating" is not a purpose of oil - lubrication (providing a film barrier helping separate components) and cooling (a constant flow of oil to remove heat) are the two main functions of oil - and they go hand in hand.
A higher viscosity oil will not flow as well (definition of viscosity) and therefore will not properly cool or lubricate components - IOW: critical components will not be provided oil at the appropriate rate of flow and pressure, ultimately starving those components of oil. An oil that is too thin may not provide the appropriate film strength.
It's a delicate balancing act that's thoroughly engineered into the engine design and why the manufacturer specifically provides a useable range in the manual. That range covers ALL operating conditions the vehicle was designed to operate in - to include track conditions: you can confirm this by checking the CR user manual - there's no other oil viscosity recommended for track use outside the normal ranges given for standard S2000s.

Any claims of "higher mileage" or 1-3 HP increases based on using one oil over another are subjective at best unless those results can be proven under strict controlled scientific conditions.

As for the post that asked for a comparison between Amsoil and Eneos - I haven't seen a head to head comparison to date. I'm sticking with Amsoil ATM 10W30 until I find a viable, scientifically verifiable test that shows there's a better oil - that also doesn't cost significantly more (I currently get my Amsoil at the Preferred Customer Program price, which is less than Castrol Edge - around the same price as Mobil 1 EP, after shipping).

foxy_s2k

I've noticed better economy and less oil burning, going from 5/10w30 to 5w40. I live in a very hot climate though.

SpitfireS

slipstream444 Posted on Jun 1 2009, 02:23 AM and Posted on Jun 1 2009, 12:55 PM

This doesn't mean your engine will blow using a 50 weight.
Btw.. how does this Eneos hold up after 7500 miles?
Is it still a 50 weight or did it shear down to a 40 weight?
I say: Why doesn't bgoetz run this Eneos for a 7500 miles, do a UOA and post the results?
Be a man!


OTOH: all dino 10W-30 oils UOA's show they DO shear down into the 20 weight range without any extra wear seen in those UOA's.
This still doesn't make it acceptable to use a 0/5W-20 in the S2000.
You probably could though.

Oil.. the debate will go on and on and on and on and on and on and on and on and on on and on and on and on and on and on and on and on and on.. and on!

INTJ

Spit and Split are right, and are actually being uncharacteristically kind. And, spitfire even broke down the visc. You can't just speculate without any sort of meaningful evidence that 50Wt is appropriate. That is not just incorrect information, it is potentially harmful.

If you have some real information, say a UOA, a SAE analysis, or a Honda tech memo, we can certainly talk in detail about this. Otherwise stop wasting bandwidth.

INDYMAC

I say try the ENEOS 0W-50 if you are all set to do it. I think the only adverse things that will happen are a loss of Hp and fuel economy. But, before you try it, why not communicate in writing with ENOES and get their blessings for your application in writing?

bgoetz

[QUOTE=INTJ,Jun 1 2009, 01:18 PM] You can't just speculate without any sort of meaningful evidence that 50Wt is appropriate. That is not just incorrect information, it is potentially harmful.