[musclecarfreak1]

I have a 1971 Chevelle with a GM 454 crate motor....wondering what the best kind of oil to put in it is...thinking about going with Royal Purple 5W-30...any suggestions?

 

[Robinls5]

If it is a new style roller engine. I would guess any good major brand.
Bob

 

[davis95]

Bob is right, but if it's a flat tappet motor you'll need an oil with a zinc additive. I'd run Valvoline VR1 20w/50 for a flat tappet engine.

 

[musclecarfreak1]

It has a hydraulic roller cam, not a flat tappet

 

[davis95]

Any name brand 20w/50 is fine then.

 

[musclecarfreak1]

So would I be alright putting synthetic Royal Purple 20W-50? Also would it be better to put in Royal Purple's multi-grain or XPR racing motor oil?

 

[davis95]

Royal Purple makes a good oil. Not sure about the XRP.

 

[Rmchevelle]

I have a 1971 Chevelle with a GM 454 crate motor....wondering what the best kind of oil to put in it is...thinking about going with Royal Purple 5W-30...any suggestions?

I'd go with the 10w-30. The 5w is a little too much like water for me. Just my opinion.

 

[musclecarfreak1]

Yeah I may even go with 10W-40...but I was just wondering if I should put in Royal Purple's reg. multi-grain synthetic oil or put in Royal Purple's XPR synthetic oil (which is for high performance and racing)

 

[Guest]

So would I be alright putting synthetic Royal Purple 20W-50? Also would it be better to put in Royal Purple's multi-grain or XPR racing motor oil?

Mult-grain?? What do you mean by that? As for viscosity, you'll never get one answer on that one. Everyone disagrees with everyone else. I'll tell you what I run and you can decide for yourself what you want to run after we have all confused you.

I run 5W30 in everything I own, with no issue at all. Everything from daily drivers, to a 600 HP Supercharged small block, to a 781 HP 540 BBC street/strip motor, with .003" clearance on the rods and mains. It survived a dyno thrash without tossing a rod, so its all good. And it maintains 80 psi oil pressure at enough rpm to reach the relief valve setting. So, that is living proof that you do not need thick oil to maintain enough oil pressure. But then I do have a Titan gerotor oil pump that flows a lot of oil.

As long as you run a premium quality full synthetic 5W30 that has outstanding film strength, you'll be good to go. I've run 5W30 Royal Purple street oil, 5W30 Royal Purple XPR Racing oil and 5W30 Castrol Edge. I like them all just fine and have no complaints, other than the RP XPR costs $14.00 per quart the last time I got some. And you have to order it from Summit or ? because regular AutoParts stores don't carry it.

5 is the cold start-up viscosity rating of the 5W30, and 30 is the operating temp viscosity rating of the 5W30. And 5 weight cold rated oil will flow quicker and better to vital engine components on start-up, than heavier 10 or 20 weight cold rated oils. And start-up is where 90% of all engine wear takes place.

If you run thicker oil, it will not flow as well at start-up, and it will not flow as well at operating temperature. And remember, an engine's vital internal components are all directly oil cooled, but only INdircetly water cooled. And thinner oil will flow more freely, carrying away more heat, thus providing better cooling for those vital components. So, 10W30, 10W40 or 20W50 would all serve your engine worse than a premium full synthetic 5W30.

Personally, I would not run anything thicker than 5W30, as long as I can get top of the line premium full synthetic oil in that weight. But I would NOT use plain old petroleum 5W30, because it is not even in the same league as the latest and greatest full synthetics.

 

[musclecarfreak1]

As long as you run a premium quality full synthetic 5W30 that has outstanding film strength, you'll be good to go. I've run 5W30 Royal Purple street oil, 5W30 Royal Purple XPR Racing oil and 5W30 Castrol Edge. I like them all just fine and have no complaints, other than the RP XPR costs $14.00 per quart the last time I got some. And you have to order it from Summit or ? because regular AutoParts stores don't carry it.

Did you notice a difference between Royal Purple street oil and XPR Racing oil???

 

[forever young]

I have a 1971 Chevelle with a GM 454 crate motor....wondering what the best kind of oil to put in it is...thinking about going with Royal Purple 5W-30...any suggestions?

If you want to know about oils, read anything SWHEATON ( scott) writes on the subject in here. He is the master of knowlege for oils. Look on some of the other subjects here and you will find his advice, and it is the best.
Roland

 

[Guest]

Did you notice a difference between Royal Purple street oil and XPR Racing oil???

Well keep in mind that the RP XPR Racing Oil should not/cannot be used in modern cat equipped cars because of its higher levels of zinc/phos anti-wear additives. Where the RP street oil or the Castrol Edge oils are intended for modern cat equipped cars or older cars that don’t run flat tappet cams.

With all that said, I haven’t run the RP XPR back to back against the RP street oil version. So, I don’t have any hard data for you about being able to tell any difference. But I think its reasonable to expect a higher level of protection being provided by the XPR under extreme operating conditions.

If you want the best protection no matter what, and money is no object, then go with the XPR. Though for the level of performance that most of us have on tap, I don’t think you’d ever be able to tell the difference between any of the 3 oils I’ve mentioned above.

There is a little more about flow that I ran out of time to mention in my earlier response above, but it is important enough to touch on now. Most folks think that pressure = lubrication, but that is simply not the case. Pressure is simply a measurement of resistance to flow. Flow = lubrication. And lubrication is what is used to separate moving parts, and keep them from touching.

If you double the flow, you will double the separation pressure in a bearing (keep in mind that liquid cannot be compressed). Pressure and flow are inversely related. A thicker oil will increase pressure, while decreasing flow. And a thinner oil will increase flow, while decreasing pressure.

Bottom line: Flow is the only thing that lubricates. Combine the extra flow with the extra cooling that thinner oil provides, and its not hard to see how the better cooling and lubricating 5W30 oils are a better choice than 10W30, 10W40, and 20W50 oils that cannot cool or lubricate as well.

 

[Autoengineer]

I'm, running Syntec 5W-40 in my engine right now. Seems like a good balance of cold weather start protection with the thicker viscosity at normal operating temps.