I run that in my 500 EFI for the last 450 hours and still running strong.

met to say 15w-50 MR driven oil. It retails for 10.99 and I buy it on a wholesale account. Anyways years ago I use to have good results thru oil analysis with VP Racing RS oils but that oil is no longer sold by VP. Again thru oil analysis in which I have a friend who does that for living plus dealing with oil analysis now for over 18 years my results have been really good with the oils I currently mentioned. Low engine wear results and very stable thru out its usage plus oxidation levels very low.

The important thing about oils is balance so that one additive is not overpowering another causing underlying problems. Next important things about oil is using the correct viscosity per your engine build and engines clearances along with staying very stable thru out running, heating & cooling cycles. Next is handling heat, condensation, oxidation & corrosion especially in a marine motor. Yes it is important to look at the data sheet specs of the oils but there is a lot more to that when oils are put to the test & time on them.

Most people get on the Bob Is The Oil Guy website and think they have become an expert about the oil ballgame. The best thing you can do with your oil is have it analyzed, use the proper viscosity, try to keep it at correct constant temps when running and change it often. Overheated oil forms high oxidation in which can thicken and form deposits on internal plus wear its additive package out very quickly, too cold of oil can not burn off condensation nor flow properly when hammering the throttles plus can form sludge and corrosion problems.

Quality oil filters and engine oil pre lubers also add to longevity and a lot better wear patterns so that's another important point to add. Also keep dirt out your motor internally or especially in marine motor, carpet fibers and that sound deadening material that dries up underside of the engine compartments. I see that a lot. The flame arrestor just caked with crap. Most boaters do not clean their flame arrestor as they think there is no dirt on the water. I do this for a living and have never seen a perfectly clean flame arrestor on a boat when it comes in. Flame arrestors are not air cleaners. Dirt and or debrie cause huge internal engine wear plus caked flame arrestors can cause rich running conditions.

Oil blenders and even oil companies have only 4 oil additive companies to buy from so yes a lot of todays oil with the proper balanced amount of additives blended are mostly all good to certain point, the 4 oil additive companies what I know of are(spelling ?) Lubrizol, Afton, Aftnite & Infinuem. Very hard to pin point which oil is best for all apps. Oils are a big opinion.

+1

No

In a big block with massive rotational parts and clearances it is crazy... Even when my oil gets old and whipped out a little the engine is significantly noisier when it starts. I wouldnt run anything less than15-40, never 10-30 and probably not even 10-40.

Just my 02. cents in my engine.

The 15w-40 and 10w-40 have the same operating viscosity when hot, so I don't really understand your opposition to using a 10w-40? A 10w-40 is a perfectly suited viscosity (especially synthetic with very few V II's) for a BBC. IMO if an oil is loosing that much viscosity to increase noise notably, you might want to look at different oils.

BUP,

I agree with most points. The one I do not though is your assumption that UOA's predict wearing inside an engine. The only way this can become useful is millions of miles of trending using a single oil and also incorporating tear downs. Obviously, this is something only fleet/trucking guys can reasonably accomplish. Also (not implying you said this) many guys think they can compare different oils with UOA's. This just isn't a good way to pick an oil, unless you have an an engine design that shears a lot or you want to get a long life oil. I think UOA's are a great tool, but mostly to monitor for big problems ie, fuel dilution, coolant excessive wear/shear, and oil change interval extension. For 99% of us, that's their only use. There are countless examples of perfectly normal UOA's in a failing/worn engine. So not combining actual tear down inspection, you are just guessing. Oil is strangely like religion... Gotta tread lightly lol

My .02, before pulling my 454 mags for rebuild I used rotella 15-40. I never had it analyzed but never thought I had too, my oil pressure was always consistent from start up to after running. On my new engines I will talk to my builder about rotella 5-40 full syn. That is what I've used in truck, cars, and track/race sportbikes without an issue.

I've ran valvoline vr1 30wt in my 598 with no problems and I'm not easy on it. If its not wide open its because I'm pulling it off the trailor. I think I'm gonna try something different with the motor over the winter and try a 5w20 in it for next season. If the clearances are right and the oil isn't getting to hot there is no need to run such thick oil. They are running 0w5 in the NASCAR stuff now and they aren't cruising around the track anywhere near 2000 rpm...

I have been running Amsoil 15/40 Deisel oil for many years. Also use a 2 quart oil filter.

VR1 is the best balance of quality and cost. $5-6/qt cant beat it.