10w30 vs 5w40 - Track Honda S2000

[Trackspec]

Need advice on choosing between 10W30 and 5W40 for my tracked 2005 Honda S2000. Car is not a serious track car - engine is stock and car only sees 5 track days in a year.

Vehicle
2005 Honda S2000
120,000 miles

Motor is healthy
Full synthetic oil only
Short oil change intervals
Owners manual recommends 10W30 while “5W40 may also be used in cold climates”

Usage
Weekend/track car that is driven 5-10k miles per year
Approx 5 track days a year
Car is driven in warm Florida climate only
Most track days are during the summer where it can get up to 100-110°F
The temp is almost never below freezing (0°C/32°F)

Since I don’t use the car is extreme conditions that often, I’m sure either grade is fine but since I have a choice, might as well make an informed decision.

I will send in a sample for UOA in about 6-12 months.

Are there any other considerations?

 

[JavierH19]

With that in mind I'd use pretty much any 30/40 grade euro, which one? it doesn't really matter you can't go wrong even with the "worst" one off the shelf if we're honest. I'm using qs 5w-40 because it's the best priced one and i order it to my door for free from walmart.

 

[Trackspec]

With that in mind I'd use pretty much any 30/40 grade euro, which one? it doesn't really matter you can't go wrong even with the "worst" one off the shelf if we're honest. I'm using qs 5w-40 because it's the best priced one and i order it to my door for free from walmart.

Thanks Javier! Why euro? My understanding is the European formulas are made for extended OCIs and are typically safe for direct injection, neither of which are beneficial to me.

I should note that I am running a test pipe so catalyst safe oils aren’t a requirement.

The car has a timing chain and based on my own research, shearing may be a factor? The redline is 8,200 and does see 8k both on street and track.

 

[JavierH19]

Thanks Javier! Why euro? My understanding is the European formulas are made for extended OCIs and are typically safe for direct injection, neither of which are beneficial to me.

I should note that I am running a test pipe so catalyst safe oils aren’t a requirement.

The car has a timing chain and based on my own research, shearing may be a factor? The redline is 8,200 and does see 8k both on street and track.

Euro oils are blended to a higher standard than regular api oils. Even if one isn't doing extended drains, have a turbo and/or direct injection it's still good to use. Better protection and cleanliness not just extended intervals go towards the blending of euro oils. 10w-30 can have an hths of 3.1 but a euro 0/5w-30/40 will be 3.5 at minimum since it needs to have a better base stock. That is what the timing chain would prefer over a standard oil.

 

[twX]

I'd recommend a euro 5W-30 or 5W-40. They'll have a higher HTHS than an API 10W-30, and you'll have a better selection of oils that have better certifications.

Oils that meet the Mercedes MB 229.51 or 229.52 standards should be good for a track car. They have more stringent foaming requirements than other standards, as well as an engine aeration test. These things can be pretty relevant to a track car spinning 9,000 rpm. They're also stringent in terms of volatility, oxidation, and piston deposits, which are also relevant to hard driving. I'd suggest Mobil 1 ESP 5W-30.

 

[thescreensavers]

Any oil meeting Porsche A40 + all the other good approvals will be good. M1 0W40 FS

 

[RAVL]

If you are doing anything worthwhile on a track in an S2000, you will be spending a lot of time at very high rpm’s - a fantastic engine. This is a situation where I would spend more money for an HPL oil in the recommended viscosity. I might want a 40 at temperature because the bottom end of those motors can fail when subjected to heavy use (seen not experienced), but I would defer to HPL or others who have used that motor.

 

[burbguy82]

Need advice on choosing between 10W30 and 5W40 for my tracked 2005 Honda S2000. Car is not a serious track car - engine is stock and car only sees 5 track days in a year.

Vehicle
2005 Honda S2000
120,000 miles

Motor is healthy
Full synthetic oil only
Short oil change intervals
Owners manual recommends 10W30 while “5W40 may also be used in cold climates”

Usage
Weekend/track car that is driven 5-10k miles per year
Approx 5 track days a year
Car is driven in warm Florida climate only
Most track days are during the summer where it can get up to 100-110°F
The temp is almost never below freezing (0°C/32°F)

Since I don’t use the car is extreme conditions that often, I’m sure either grade is fine but since I have a choice, might as well make an informed decision.

I will send in a sample for UOA in about 6-12 months.

Are there any other considerations?

Nice car, one of the most underrated for sure. Wish I could get my hands on one. Where are the pics of this car?

 

[ChristianReske]

Oils that meet the Mercedes MB 229.51 or 229.52 standards should be good for a track car. They have more stringent foaming requirements than other standards, as well as an engine aeration test. These things can be pretty relevant to a track car spinning 9,000 rpm. They're also stringent in terms of volatility, oxidation, and piston deposits, which are also relevant to hard driving.

Very Interesting. Where can i read about it? Source, Link?

 

[ChristianReske]

In Germany, no S2000 owner uses a 0w- oil. I wouldnt also, because the engine has a insane piston speed. 25.2 Meters (82,67 Feet) / Second for the F20 C engine or 24.2 Meters (79.4 Feet) / Second for the F22 C engine. You want a shearstable oil. 5w- or 10w- , MB229.5 or Porsche A40 Approval.

See: https://en.wikipedia.org/wiki/Honda_F20C_engine

In Germany, every Honda S2000 uses 5w-40, including mine. The engines last, even use on the Racetrack. There was a Poll in the german S2000 Forum. Most members use the real PAO Liqui Moly 5w-40. Here is the Excell sheet of the Poll:

As you have removed the cat, you could also try to use a racing oil. 5w- 10w- Redline , HPL, Valvoline VR1, what ever.

Have fun!

 

[Olinskis]

If not a euro 40, would a 10w30 diesel synth oil be an option? There's good ones from hpl and amsoil. Even rotella and delvac off the shelves.

 

[ChristianReske]

What is all the fuzz about diesel oils in Car / Motorcycle Gasoline engines? I really dont get it.

Second post in this Thread says it all: https://bobistheoilguy.com/forums/threads/m1-0w-40-fs-vs-rotella-t6-5w-40.376388/

 

[wings&wheels]

IIRC, Honda recommended 5w-40 for markets outside of the US and maybe Canada?? I ran mine on Redline 5w-40.

 

[DV0993]

Fellow s2000 owner here. 5w40 without a doubt - All my UOAs have been better with a 40 weight.
Track use similar to yours.