Best Engine Oil - All Mod Levels

Here's my latest UOA on Royal purple 1037km 6 months, very short runs like 7km or so in -20c or below rarely get to operating temps also doesn't get driven and can sit for a week before going anywhere, I did rebuild hpfp and replace injector seals. Looking back when I did more summer driving and highway driving I don't seem to get as much fuel dilution so I'm thinking it's just from lack of driving and lack of driving at operating temps .

Gen2 speed 3, original stock block
 

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All of this RP talk interests me, since I was fucking dragged on Facebook for posting my Blackstone oil analysis, one batch of which was RP. People hate on it because it SOOOOO expensive. When, in fact, it's really not that much more than Pennzoil, Mobil 1. It's not Amsoil / Liquid Moly expensive, and my analysis showed that it played
well with my engine.

When I get home later, I'll share my string of Blackstone charts. I know I have RP, brotella, Pennzoil, and possibly a Mobil 1. My last 2 analysis showed fuel dilution and low flash points, but I've since replaced my injectors, and added seals.
 
So i live in Phx Arizona where the temperature can get up to 115 degrees in the summer. Should i go with a higher oil weight like 5w40??? if so any brand recommendations in that weight class
 
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So i live in Phx Arizona where the temperature can get up 112-113 degrees in the summer. Should i go with a higher oil weight like 5w40??? if so any brand recommendations in that weight class
You can if you want, if you read your manual it tells you the temp ratings of various weights for the engine. There was a TSB to run 5w40 for gen1 for leaking turbo seals so won't hurt might help. I don't typically run 5w40 and I see 108f here. Also if you looked at any of the brands on the list you'll see that all but Pennzoil platinum comes in 5w40, it does come in platinum euro 5w40, just pick one and do a short interval change when swapping oils
 
So I did a bunch of research on 40 w oils. If you are trying to stay with all of the recommended Dexos standards for our motor you will not find them in a 40 w oil.

40 w oils are marketed for European cars that do not have the LSPI issues the Speed motor can have. I probably make a bigger deal out of this that it really is but my long block was not cheap.

That being said I am on Amsoil SS 0w40 because I was having oil pressure issues with my built motor on the Dyno.

If you really want to figure this out you need to snoop around on Bob is the Oil Guy forums.
 
I just want to say... Give me a break, I'm sure I did at least an autocross session, drove it like a stole it nearly everyday, and this is probably the longest interval I have and will ever do, not something I planned on.

Alright, so I seem to hear hate on Mobil1 but I've never really seen anything on the WHY.
My numbers seem to be fine on this UOA considering the extra long interval I had on this. I want to say I was NORMALLY running 5k-6k intervals on oil changes. I'm using Mobil1 5W-30 High Mileage, and as this was from the end of 2015, so I would assume this was API SN+ but maybe even SN rated.
The report for my miata (2022 so likely API SP) shows similar numbers for moly/zinc, sodium, calcium.

I never had any issues with the motor up just above 200k and after pulling apart to build even the machine shop had comments on how little wear there was for 200k+ (stock) performance engine.

Engine is apart to build it and start putting down more power, which is why I'm now starting to research what oils I should potentially run after my break-in.
 

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Mobil 1 isnt a bad oil it is just not actually a true full synthetic. it is a synthetic blend that is sold at a premium price as if it is full synthetic. instead of paying for good oil you are paying for decent oil and a shitload of marketing
 
I've been trolling BIOTG for a bit.

Valvoline 5w30 Extended Protection looks nice.

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D1G3, API SN+ and SP, ILSAC GF6A. Calcium is in check, moly is higher than what I typically see, zinc is high. cSt isn't bad either.

HTHS 3.2 on valvoline site

I was kind of looking for an oil that is both D1G3 and ACEA A3/B4. But I can't find such a thing.

I'm not sure why they are seem mutually exclusive. I have noticed the euro oils with the A3/B4 tend to have high sodium though.
 
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I would strongly suggest installing an oil pressure gauge on a built motor. Mine alerted me to lower than desirable oil pressures running PP 5-30.
Just curious what pressures you considered low? I didn't realize until installing mine that a normal idle pressure (warmed up) is only from 5-10psi.
 
So I was on the dyno with oil temps at 220 F and we were seeing 5-6 psi at 850 idle. Matt @ Damond had Will bump my idle to get through the tuning session but I switched to Amsoil SS 0-40 after that and it solved my problem. I also ran RP 5-40 for a short period as well before the Amsoil and it also performed well from an oil pressure standpoint. I see about 12-14 psi at 850 idle now with oil temps at 220 F and I fall in the range that the FSM specifies.

Per the FSM

Oil pressure (reference value) [oil temperature: 100°C {212 F}]
LF: 234-521 kPa {2.39-5.31 kgf/cm2, 34.0-75.5 psi} [3,000 rpm]
L5: 395-649 kPa {4.03-6.61 kgf/cm2,57.3-94.1 psi} [3,000 rpm]
 
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Low oil pressure at idle is definitely less then ideal.

Typically “warm” or “hot” idle is going to be no more then 170-190f. if you already have lower pressures at this temperature that’s a problem.

You’re gonna have some trouble when oil temp reaches 220+.

For me this was always a consideration due to track usage. Coming off track oil temps 230+ were common. If the car only made 10psi at 180 what happens at 230? Trouble. Been there done that.

In terms of messing around with oil clearances? Don’t. Just stick to what the manual recommends. If you’re leaving extra clearance there must be a reason for that beyond “shits worn”. That’s not a good reason. This is usually done to run a specific oil weight for race purposes.

The clearances in the manual assume a 5w30 oil.

Anyways. Heavier oil helps. Higher idle helps
 
So I’m wondering about liqui moly 5w40. Been running it for 12k miles, and I found it on some forum that did a UOA and it was really good. Its API SP which should be better than API SN+ right? Im mostly stock but im pretty sure this oil should be great, I’ll try to check for sodium levels and stuff but I definitely feel like it should be mentioned and I’m going to get a UOA on my next change, trying to figure out a sheering issue right now, oils reeks of gas, and I think I figured it out, stage 1 cobb ots. Anyway ill do a change or two more and get 3000 mile UOA done and send it here.
 
If the oil reeks of gas, it's not the right oil for the platform. That basically means that it will have a high fuel dilution % which will help cause LSPI.

Unless you're doing 5 min quick trips and the oil isn't coming up to temps, this is a symptom of a garbage oil (for DI, probably excellent for other platforms). Also if you are doing 5 min quick trips, stop it. You're killing your car quicker than you think.
 
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