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Which oil? Mineral vs Synthetic

66 Sat,
Post #10. If your engine builder recommended 25/70 oil for a recond engine with factory clearances, then he is still a dope. For two reasons:
- the oil is too thick when you want oil to flow quickly to new parts
- break in oil has the correct additives in it for new parts to break in. If break in oil was not needed, why would they make it????
Penrite recommends 25/70 for worn engines with wide clearances, not newly rebuilt fresh engines.
The benefit of a 10/60 oil over a 20/60 oil is that the 10 oil will flow more quickly [ thinner ] @ 0*C than 20/60.
Zinc/Ph amounts vary between companies as there does not seem to any std. 800-100 ppm or more is good.
Non-friction modified. Thank the US EPA for that! Myself & friends racing in the 70s used to use BP Corse +. It was considered one of the best at the time. Over a period of a few months, we noticed our idle oil pressure had dropped. All our engines were suddenly not faulty! I rang BP & was told the oil was NOW friction modified. The oil was made thinner to pass EPA mileage tests in the US. Penrite performance oils are proudly non-FM & do not thin out as much when they get hot.
In the general engine section of Speedtalk.com, there is currently a thread on oils with an expert commenting. He would NOT be happy to hearing about 25/70 oil.....
 
Some big name full syn oils did badly: Redline.
You think so ??

37 R.JPG


Re-Rebuilding the 440-493 in a 1970 Charger
 
66 Sat,
Post #10. If your engine builder recommended 25/70 oil for a recond engine with factory clearances, then he is still a dope. For two reasons:
- the oil is too thick when you want oil to flow quickly to new parts
- break in oil has the correct additives in it for new parts to break in. If break in oil was not needed, why would they make it????
Penrite recommends 25/70 for worn engines with wide clearances, not newly rebuilt fresh engines.
The benefit of a 10/60 oil over a 20/60 oil is that the 10 oil will flow more quickly [ thinner ] @ 0*C than 20/60.
Zinc/Ph amounts vary between companies as there does not seem to any std. 800-100 ppm or more is good.
Non-friction modified. Thank the US EPA for that! Myself & friends racing in the 70s used to use BP Corse +. It was considered one of the best at the time. Over a period of a few months, we noticed our idle oil pressure had dropped. All our engines were suddenly not faulty! I rang BP & was told the oil was NOW friction modified. The oil was made thinner to pass EPA mileage tests in the US. Penrite performance oils are proudly non-FM & do not thin out as much when they get hot.
In the general engine section of Speedtalk.com, there is currently a thread on oils with an expert commenting. He would NOT be happy to hearing about 25/70 oil.....
Well I still trust his knowledge gained in building engines for the last 40 or so years. No reason for him to recommend the wrong oil, maybe he knows more than you credit him for.
Interestingly Penrite themselves offer different advice than you did in post #9, which proves you aren't the authority on everything either.

Thanks for your inquiry, HPR 30 is a great product for this application. Just keep in mind Mineral oil needs to be replaced more frequently 3-5,000 Km.

Once the Engine has 10,000 Km plus you could consider using 10 Tenths Racing 20 20W-60.

Kind Regards

Jamie Rodger

Technical Support

Penrite Oil Company

T 1300 PENRITE (1300 736 748) | F +61 3 9801 0977 |
[email protected]
 
66 Sat,
Ask Jamie Rodger:
[1] how many engines he has built
[2] How would he detect bore glazing from using the wrong oil.

At the same time, ring a few other engine builders & see how many recommend 25/70 as an initial oil fill.........
 
Kern Post #22.

This is what the test report said on 5w-40 Redline:-

'This was the second most expensive oil on the test, so we expected it to perform - especially with the boasts from the manufacturer. Put simply, it didn't with the film breaking with 6lb on the lever & a scar length on the test bearing of 6mm. Its extreme pressure properties were not as good as some of the far less expensive oils..'
 
I'm thinking there has to be a difference in the way oils are rated in Autralia, compared to US. If not, 20/70 is way too heavy. I was given some straight fifty weight racing oil, it can pass for maple syrup.
I use full synthetic in the new pony car that requires it. I use diesel in the diesels. I use mineral oil in the old cars, usually a mix of diesel and auto oil, for the zinc. I broke in my 440 with a witches brew of diesel, some pennzoil racing, some 10/40, and a breakin additive. I don't recommend that technique to anybody, but it worked for me, and it was all stuff I had in the garage.
 
I am so confused now. I thought mineral oil was what you gave a horse when he was having stomach trouble. I thought all engine oil was made from crude oil that is pumped out of the earth. I thought synthetic oil was just some other process of refining crude oil. I thought anything mixed with zinc is good for flat tappet cam motors, and anything with a catalytic convertor, just doesn't have the zinc. Lots of people run "diesel oil" in flat tappet motors. What are they made out of? What is the difference between "parts store" 20w -50 and zinc additive, and Valvoline VR1 with high zinc?
My current strategy is 20-50 with zinc additive, in my flat tappet gas engines, regular 10 w 30 in my '07 GMC LS motor, and regular 15w 40 in my old Farmall tractor.
 
I am so confused now. I thought mineral oil was what you gave a horse when he was having stomach trouble. I thought all engine oil was made from crude oil that is pumped out of the earth. I thought synthetic oil was just some other process of refining crude oil. I thought anything mixed with zinc is good for flat tappet cam motors, and anything with a catalytic convertor, just doesn't have the zinc. Lots of people run "diesel oil" in flat tappet motors. What are they made out of? What is the difference between "parts store" 20w -50 and zinc additive, and Valvoline VR1 with high zinc?
My current strategy is 20-50 with zinc additive, in my flat tappet gas engines, regular 10 w 30 in my '07 GMC LS motor, and regular 15w 40 in my old Farmall tractor.
The only thing I'll add is that the LS motors were spec'd for Dexos1. Anti sludging properties I presume.
 
That is another new one to me, Dexos1. Is that a type of oil, a brand name or an additive?
 
Amsoil is one of maybe 3 true synthetics. It begins life in a lab, not with Dino. The rest transition in processing. They are not truthful in advertising. Like a used car with an off center steering wheel, it’s a good indication that something else is wrong.
 
I am so confused now. I thought mineral oil was what you gave a horse when he was having stomach trouble. I thought all engine oil was made from crude oil that is pumped out of the earth. I thought synthetic oil was just some other process of refining crude oil. I thought anything mixed with zinc is good for flat tappet cam motors, and anything with a catalytic convertor, just doesn't have the zinc. Lots of people run "diesel oil" in flat tappet motors. What are they made out of? What is the difference between "parts store" 20w -50 and zinc additive, and Valvoline VR1 with high zinc?
My current strategy is 20-50 with zinc additive, in my flat tappet gas engines, regular 10 w 30 in my '07 GMC LS motor, and regular 15w 40 in my old Farmall tractor.
There are different grades of oils, not all come out of the ground. Cheap stuff is Group I, which is adequate for old engines and some slow marine use. Group II is a little better, usually what you'll see on big box store shelves as conventional oils, making up nearly half of the engine oil sold.

Group III is really highly refined crude oil, reconstructed at the molecular level and so good that it can pass most requirements for synthetic. It didn't use to be called synthetic (because it isn't) until some big oil lobby groups got the rules changed in court. (Check out the lawsuit where Mobil sued Castrol for calling their type III synthetic. Castrol won that case, changing the rules.)

Group IV is a real synthetic, created not from crude oil but instead built up from polyalphaolefins. No need to refine out wax, sulphur or nitrogen components because they weren't there in the first place. Most polyalphaolefins are created in the lab from ethylene. A common source to create the base stock from is natural gas, as shown in this example:
1671076850773.png
 
This works for me living in a temperate zone. It also comes in 20W-50.

images-3.jpeg
 
I’ve been using Mobile 1 high mileage 10w-40 in my 383. It’s just a daily driver though.
 
Oh man, oils! What a can of worms!
Here is my experience in life, i do not claim to be an expert or something:
Growing up on the farm, we put CENEX 30 weight into all the tractors. The one that got winter farm chore duty might get 20 weight for those months if winter came early and promised to be extra cold. That was 30 years ago and then some. I still have the old gasoline powered MM U302. I don;t field work it. It gets more use on snow duty then otherwise. Last changes I put Mobil Delvac 15/40 in it. One of the few rated for older engines anymore, Shell Rotella was too but I haven't checked that one recently. My tractor was bought new in 1966 by my Grandpa and then farmed at Dad's farm and now I have it. So it get's babied.

My tow rig is an 8.1 Chevy with Allison trans. Calls for 5w30 on it. Low RPM's mostly and low miles per year means I change the oil before it is bad. So I don't buy super cheap for it but I tend to get whatever is on sale between the few brands I like. Usually that means Shell Rotella, but I used Castrol a couple times.

Otherwise in recent years most things get Mobil 1. My '13 Charger likes it, I switched to a cheaper oil(house brand) for what ended up being a 1500 mile oil change because I could actually tell the difference in how it ran after that long and the engine had consumed a little which was something totally new. Won't do that again. People like to say new engines don't care what oil you put in and all the manufacturers are the same but that's BS.
The 94 Mustang I had got Mobil 1 for as long as I had it and previous owner said he used it starting at 40k miles when he got it. My boy has it now, 170k miles of getting beat to piss and no oil consumption. Yeah, I drove that car hard, redlines in second gear for anywhere I could go over 45mph, which by me is everywhere :)

One brand I stay clear of is Pennzoil. I just don't know how to interpret their products anymore, and back in the day when it was just Pennzoil without whatever flashy labels and branding on it my family used it basically 100% for vehicles(except farm truck). Mostly because both Grandparents had used it forever. So my Dad did too.
Then in the 80's, my Ma's Caprice wagon wore out a camshaft. Well that's what the repair guy said. Wore it out far enough it wouldn't run anymore. Replaced it and back in business(that car ran forever) Then we had a mid 90's Buick LeSabre. 3800, but it started getting loud at 140k miles. Younger brother drove that and the engine eventually gave up. There are a couple more examples(not all GM products) of weird wear with valvetrain on engines known to run for a longer time then we were getting. Other vehicles like my older Sister's had gotten oil changes at the corner shop out of town with other brands and had worn normally.
So sometime in the late 90's my Pa and I decided maybe it was the Pennzoil. The wear was all similar, and it seemed to be the only common thing. We reminisced about my Grandpas, but they both really only ever drove 45 MPH on the country roads up here and never pushed their cars. So it would seem old Pennzoil was really good for easy living cars in the cold up here, but when the vehicles were driven a bit more normally(or harder with a bunch of teen drivers in the house over the years) it didn't do so hot with warm engines and the valvetrain suffered. So I haven't ever bought it. And I don't even know what they offer because every time I see it there is a new color label with different lingo on it.

I was told horror stories about Quaker State in the 1980's. honestly never tried that one, the others I mentioned above are doing fine by me so I have no reason to.
 
Pennzoil and QS used to be the same company way back when before Shell purchased the company.
When my son was a teen he got a job at a quick lube place which used Pennzoil. He could tell which cars used Pennzoil exclusively. The insides were all filled up with deposits. Just pull the oil cap and look inside. Nothing but gunk.
That may be different now.
As for the Dexos 1/2 labeling, it's all a money making scam.
GM got this idea to require this new spec oil, but many oils already met the spec but the oil had to be tested for that spec. But to get the Dexos label you gotta pay GM for its use.
 
{ yawn } ... 10W-40 conventional (pick-a-brand), add STP, for over 50 years. Nowadays, adding ZDDP. Good night.
 
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