New passenger car diesel oils = Better protection for older gasoline engines?

Interesting Read: https://blog.k1technologies.com/bearing-clearance-and-oil-viscosity-explained

Hondas recommendation of a -30 viscosotiy and the bearings clearances in the workshop manual of the S2000 matches these results.

And here is more: https://www.enginebuildermag.com/2013/03/bearing-clearances/

"Reducing the oil clearance between the rod and main bearings and the crankshaft has a number of advantages. A smaller gap spreads the load over a wider area of the bearing surface and distributes pressure more uniformly across the bearing. That’s good, provided the bearing is strong enough to handle it. A smaller gap also decreases the volume of oil that has to flow into the bearing to maintain the oil film between the bearing and shaft.


That’s also good, provided the oil is thin enough (low viscosity) to flow well into the bearing. This also reduces the amount of oil pressure the engine needs, so some extra horsepower is gained by reducing the load on the oil pump."

Interesting read!

The last two reports about damaged engines in the german S2000 Community had two things in common:
Both owners tried to reach top-speed of the car on the autobahn and both used -50 (!) oil.

I trust the engineers at Honda, i will use a thick 30 - thin 40 Oil, viscoity range 11-13 KV 100°. And i will never press the car to the limit on the autobahn, i am convinced that this engine is not safe for long time full throttle runs because of the insane piston speed at 9000 RPM.
 
Interesting Read: https://blog.k1technologies.com/bearing-clearance-and-oil-viscosity-explained

Hondas recommendation of a -30 viscosotiy and the bearings clearances in the workshop manual of the S2000 matches these results.

And here is more: https://www.enginebuildermag.com/2013/03/bearing-clearances/

"Reducing the oil clearance between the rod and main bearings and the crankshaft has a number of advantages. A smaller gap spreads the load over a wider area of the bearing surface and distributes pressure more uniformly across the bearing. That’s good, provided the bearing is strong enough to handle it. A smaller gap also decreases the volume of oil that has to flow into the bearing to maintain the oil film between the bearing and shaft.


That’s also good, provided the oil is thin enough (low viscosity) to flow well into the bearing. This also reduces the amount of oil pressure the engine needs, so some extra horsepower is gained by reducing the load on the oil pump."

Interesting read!

The last two reports about damaged engines in the german S2000 Community had two things in common:
Both owners tried to reach top-speed of the car on the autobahn and both used -50 (!) oil.

I trust the engineers at Honda, i will use a thick 30 - thin 40 Oil, viscoity range 11-13 KV 100°. And i will never press the car to the limit on the autobahn, i am convinced that this engine is not safe for long time full throttle runs because of the insane piston speed at 9000 RPM.
I would be more concerned with your valve retainers.
 
Allready upgraded. :cool:
Hey, i am german and mechanic, what do you think was of course the first thing i have done after i bought it? ;)
Partly dissasembling the engine! :LOL:
 

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That almost sounds like a big bike engine, 4cyl water cooled, FI, high rev limit. Have you given any thought about a motor cycle oil eg castrol Power 1 racing 10w30 or 10w40. I used the old RS in the CBR1100, Fireblade, and CBR 1000, it held up fine on long trips running 7-10k rpm.
 
Allready upgraded. :cool:
Hey, i am german and mechanic, what do you think was of course the first thing i have done after i bought it? ;)
Partly dissasembling the engine! :LOL:
Well you're already there then!

I remember getting pulled over on Easter after exiting a small village (briskly) with my S2K. PWJDM intake + Invidia long tube headers, test pipe, and 70mm single.

Ze Polizei: "You cannot have zis. It is too loud."

🤣

Chain tensioner done too?
 
I found this EXTREMELY interesting since I use 5w-20 in my 1993 F150, 2000 4Runner and 2005 Ranger. They were all "back spec'd" to this viscosity. I checked the crankshaft oil clearance tolerances on all three vehicles and they fall into the range for 5w-20. My Dodge B2500 van falls into the 5w-30 range which is what I use.

Sorry for hijacking the thread but I found this information useful. Thanks for the links!!!

From the link:

Bearing Oil Clearance Chart
Oil ViscosityRod Bearing
Clearance
Main Bearing
Clearance
20w / 5w20< 0.0021TD]
30w / 5w300.0021 – 0.00260.0020 – 0.0025
40w / 10w400.0026 – 0.00310.0025 – 0.0030
50w / 20w500.0031 >0.0030 >
[TD]
Common sense dictates that bearing clearance directly affects oil flow with predicable results. Reducing the clearance will increase the restriction to flow and reduce the volume of oil past the bearing. Because of this reduced flow, the localized bearing temperature will increase. If this temperature exceeds the oil’s thermal stability limit, the oil will begin to oxidize and break down, reducing its ability to lubricate.
 
That almost sounds like a big bike engine, 4cyl water cooled, FI, high rev limit. Have you given any thought about a motor cycle oil eg castrol Power 1 racing 10w30 or 10w40. I used the old RS in the CBR1100, Fireblade, and CBR 1000, it held up fine on long trips running 7-10k rpm.
It really can sound like a bike... ;)



Regarding the oil, peole here at Bitog told me not to use bike oil because it dont contain friction modifiers, thanks to the wet clutches used in bikes. :unsure: However, while i am really not a big fan of the Brand, i think i will give the Ravenol RSP a try.
 
Well you're already there then!

I remember getting pulled over on Easter after exiting a small village (briskly) with my S2K. PWJDM intake + Invidia long tube headers, test pipe, and 70mm single.

Ze Polizei: "You cannot have zis. It is too loud."

🤣

Chain tensioner done too?

Hey, do you make jokes about the way we germans speak the english "TH"? :ROFLMAO:
Was your car registerd in the US or in germany?

Chain tensioner is next, will try to get one from Billman soon.
 
I found this EXTREMELY interesting since I use 5w-20 in my 1993 F150, 2000 4Runner and 2005 Ranger. They were all "back spec'd" to this viscosity. I checked the crankshaft oil clearance tolerances on all three vehicles and they fall into the range for 5w-20. My Dodge B2500 van falls into the 5w-30 range which is what I use.

Sorry for hijacking the thread but I found this information useful. Thanks for the links!!!

You are welcome. No problem. :)
 
Was your car registerd in the US or in germany?

German based US military member's civil cars use German style license plates.
You may call it "undercover".

So you've decided to stay with a more traditional full SAPS formulation (like RSP)
instead of trying a "new passenger car diesel oil" (REP/RUP) as the title suggests?
What's the reason?

.
 
German based US military member's civil cars use German style license plates.
You may call it "undercover".

So you've decided to stay with a more traditional full SAPS formulation (like RSP)
instead of trying a "new passenger car diesel oil" (REP/RUP) as the title suggests?
What's the reason?

.

Will the new oils perform better? I am unsure.
 
the new oils need PAO to perform like the old formulations made witrh grp III. But you can have the old formulations with PAO/POE aswell....
 
I found this EXTREMELY interesting since I use 5w-20 in my 1993 F150, 2000 4Runner and 2005 Ranger. They were all "back spec'd" to this viscosity. I checked the crankshaft oil clearance tolerances on all three vehicles and they fall into the range for 5w-20. My Dodge B2500 van falls into the 5w-30 range which is what I use.

Sorry for hijacking the thread but I found this information useful. Thanks for the links!!!

From the link:

Bearing Oil Clearance Chart
Oil ViscosityRod Bearing
Clearance
Main Bearing
Clearance
20w / 5w20< 0.0021TD]
30w / 5w300.0021 – 0.00260.0020 – 0.0025
40w / 10w400.0026 – 0.00310.0025 – 0.0030
50w / 20w500.0031 >0.0030 >
[TD]
Common sense dictates that bearing clearance directly affects oil flow with predicable results. Reducing the clearance will increase the restriction to flow and reduce the volume of oil past the bearing. Because of this reduced flow, the localized bearing temperature will increase. If this temperature exceeds the oil’s thermal stability limit, the oil will begin to oxidize and break down, reducing its ability to lubricate.

Just checked what the bearing clearances are for my engine. 0.0015 to 0.0040. guess it needs anything from 0w16 to sae60
 
Some newer diesel oils are no longer gas engine rated. So you need to make sure.
the gas rating is only important in Di only engines. in an old port injected engines id run a diesel, in an early DI only engine id stick to the dual rated oils like delo which have a lot less calcuim and a lot of magnesium and i have seen them be run in early ecoboosts without lspi.
 
mb 229.5 oils are basically dual rated and and in that s2000 id say yes go ahead. I'd recommend supertech diesel as its volvo vds certified for long oxidation resistance and ford wss certified for higher anti wear and is really good. id also go for travelers or the tried and true t4. all are vds and wss certified.
 
the new oils need PAO to perform like the old formulations made witrh grp III. But you can have the old formulations with PAO/POE aswell....

The mentioned Ravenol RSP (LL-01; MB229.5) and the equivalent mid-SAPS Ravenol REP (LL-04, MB229.5, 229.52) are similar in base stock (perhaps with minor advantages towards REP, at least that's what the data sheets suggest). Main difference is in Phosphorus, Zink and Sulphur (sulphated ash 1.24 vs 0.8.%wt). RSP is HTHS of 3.57 mPas, while REP is 3.7 mPas, both are 12,2 cSt at 100°C. Noack is 7,2 % for RSP and 6,2 % for REP. Hopefully that explains why I use REP in two of my cars.


.
 
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I'd recommend supertech diesel

I doubt Supertech is sold in Munich. No need to hassle with Volvo approvals. Plenty of choice on BMW, MB and VW or even Porsche approved oils in Germany.
Did I mention Porsche? Ravenol RUP got BMW LL-04, VW 511 00, MB 229.51 and Porsche C40 approvals. Hard to beat. That's probably what I'd try in this S2000 first.


.
 
It really can sound like a bike... ;)



Regarding the oil, peole here at Bitog told me not to use bike oil because it dont contain friction modifiers, thanks to the wet clutches used in bikes. :unsure: However, while i am really not a big fan of the Brand, i think i will give the Ravenol RSP a try.

I spoke to Castrol about that years ago, I was getting the RS MC from Louis for DM25 for 4 ltr and wanted to use it in my E30 M3 with S14 engine. They said it was no issue whatsoever, it is not different than using a diff oil that contains a limited slip additive in a non LS diff.
They basically said do do the opposite (car oils in MC) although many people use car oils in MC seemingly without any issues.

When I think about it, what is the difference? Both have a crank, cam(s), cam chains, oil pump, rocker arms, lifters/ lash adjusters or shims.
The car engine is missing the wet clutch and in most modern bike engines the gear box.
I ran my brand new SC24 Euro spec out of Holland still in the crate (Germany still had a 100HP limit at that time thanks to the CBX), I broke it in on dino slowly (not over 4K rpm per owners manual for the first 400km) for the first 1K then switched it over to RS, it never had any other oil or any other rider.
I ran it over 240K km over 12 years and ran hard, lots of high speed Autobahn use, at 240K I did the cam chain which required splitting the cases, no bearing scoring or cylinder wall wear, all measurements were in new engine spec according to the FSM.

Imagine that on a 10w60 of all things, the transmission and long term high rpm really beat the oil up bad which is not an issue with your car, no need for an oil that heavy.
The engine had a min oil pressure of 7bar. The 4 cyl M3 never had any issues, it ran for many years on the RS without complaint, its bearing clearances were designed for heavy oil.
 
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