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Author Topic:   SAE 50
copper
Member
posted June 10, 2004 09:04 PM
DOES ANYBODY USE SAE 50 VALVOLINE VR1 RACING OIL. INSTEAD OF 20W 50 I HAD SOMEONE GIVE ME SOME AND WAS WONDERING IF I SHOULD USE IT IN A 355 CHEVY PURE STOCK CAR. IF NOT WHY? THANKS.


racing33A
Member
posted June 11, 2004 05:01 AM
I have used that exact oil before without any problems. I recently switched to a 40wt oil just because I was thinking that maybe the 50wt was to thick. Both have worked good in my 355cid.
racing33A


NJantz
Member
posted June 11, 2004 07:10 AM
It wont necessarily hurt anything but your prob giving up some HP over a 20w50 oil. Also make sure the engine is up to full operating temp before racing so that you arent trying to pump the heavy cold oil at high rpms. (good rule of thumb for any oil)


outlawstock17
Member
posted June 11, 2004 02:29 PM
i think you might have that bassakwards, njantz.....20w-50.....50 is as thick as it will get when it's cold and 20 is as thin as it will get when it's hot...


mod70
unregistered
posted June 11, 2004 03:13 PM           
I run VR1 50w all spring and in the fall when it's cooler. In the middle of the summer when it's over 90 to 100 deg I'll switch to 60W. Same thing my teammate does and neither of us has ever had an oil related problem. Bearings look perfect at end of the year teardown.


johnrhonda
Member
posted July 03, 2004 12:54 PM
i use 50w vr1 and the only problem i have is that it takes so long to put it in the engine it takes a long time.


beachracing
Member
posted July 03, 2004 03:24 PM
I have used 20w50 valvoline(race)oil in the silver quart, and never had a problem.If you have a lot of clearance it's a safe bet to go with a high viscosity.The valvoline 20w50 also has ZDDP which is a zinc additive which helps fill the tiny microscopic scratches on surfaces.I turned a motor 7 grand, and bearings were in great condition.Change every three races, and use it in your hauler.Use a high volume, and not high pressure pump in regular applications.


6pack
Member
posted July 03, 2004 03:39 PM
Outlawstock17 YOU have it Backwards 20w50 oil Has The viscosity of straight 20w when cold, But, Resist thinning and Is The same Viscosity hot, As a straight 50w hot. Thats why there is Multi Viscosity Oils, to Have thin Oil For Easy Pumping cold But Not To Thin hot... The best of both worlds Except For the "not As Stable As Straight weight" thing, But thats so "70's". Why Not Amsoil Synthetic Anyway.?


bigcityracer
Member
posted July 05, 2004 10:17 PM
Tom Waara Your dead wrong. Outlaw17 is correct.
The high number represents the cold viscosity.
The low number is for hot.

Think about this then, when the motor is cold your oil pressure is high then when it drops the pressure is lower.

Raz_900
Member
posted July 05, 2004 10:41 PM
quote:
Originally posted by bigcityracer:
Tom Waara Your dead wrong. Outlaw17 is correct.
The high number represents the cold viscosity.
The low number is for hot.

Think about this then, when the motor is cold your oil pressure is high then when it drops the pressure is lower.


Hate to tell ya but BigCity but you and Outlaw are the ones that have the numbers backwards.
http://www.chevron.com/prodserv/nafl/auto/content/motoroils.shtm

SAE (Society of Automotive Engineers) Viscosity Grade
Viscosity is a measure of an oil's thickness, or resistance to flow. Lower numbers indicate thinner oil and higher numbers indicate thicker oil. There are two types of motor oils, single grade and multi-grade. Multigrade oil such as a 10W-30, are designed to have the viscosity of an SAE 10W oil at cold temperatures combined with the viscosity of an SAE 30 oil at engine operating temperatures. The "W" or "Winter" designation indicates that the oil meets viscosity requirements for low temperatures (below 30 F)."

So, a 20w-50 would behave like a straight SAE 20w grade oil below 30 degrees and like a straight SAE 50 grade oil at 100 degrees C or 212 F (that's the testing limits, 0 and 100 degrees C).

I happened to do lab tests on oils when in college and the SAE definition of their standards is correct.

[This message has been edited by True Blue (edited July 05, 2004).]

dirtbuster
Member
posted July 06, 2004 08:18 AM
I agree with Raz. Its not that the 20w50 actually becomes 50wt oil at high temperature jsut that it doesnt thin out more than a 50 wt oil would. Presssure will always be higher when oil is cold no matter what weight it is. An oil no matter what will pump and flow easier when warm. Thats why you should make sure you engine is warmed up completely before hitting the track. Ours doesnt get raced until it hits 180 or better.


bigcityracer
Member
posted July 06, 2004 12:52 PM
WELL!!!
I am DEAD wrong!! Never been to proud to learn new things and I did go to the web site and read it. My apoliges go out to Outlaw17. Sorry just thought I knew that one.

Razz_900 Thanks for the correction.
Not good to have wrong info passed around, we all have enough problems.


bigcityracer
Member
posted July 06, 2004 01:08 PM
Well now that I find I know nothing about oil again, I have a couple questions.

#1 First number is the weight of the oil and the second is the viscosity?

#2 So would a SAE30 be kind of equal to a make beleive with me here. (SAE30W 30)


dirtbuster
Member
posted July 06, 2004 02:10 PM
bigcity,
1. Both numbers are ratings based on viscosity, the number itself is not the actual vicosity which is measured in centistokes. The viscosity of a given oil is measured in a lab then weighted according to a chart. That means that if an oil falls within a range of 16.4-21.8 centistokes at 212F degrees then it would be considered typ of a 50wt oil even though some oils may be closer to 16.4 and some closer to 21.8 they would all be considered 50 weight. Thats where the 10, 20, 30 ,50 etc numbers come from. (Here is a link to the a viscosity chart, http://www.bobistheoilguy.com/visc.html
2.I think i understand what you are saying and yes that would be right they just dont put the second number on there because its not needed. But yes a sae 30 oil means that it fits into the range of typical 30 weight viscosities at both 32 and 212 degrees. The advantage to multi viscosity oils like a 20w50 is that at cold temperatures it behaves like a regular 20wt oil would, easy to pump and flow through the engine. Plus at operating temp it wont be any thinner than a straight 50wt oil would be so it has the load capacity to protect the engines internals. The drawback is that in order to make the oil work that way it requires additives and as the oil is used these additives are depleted. The more split between the numbers the more additive is needed. A 10w40 will require more than a 15w40.

Also i feel the reason most saturday night racers need the heavier oil is because of the oil temps up to or more than 300F degrees. At that temp the 50wt oil's viscosity is porb closer to that of a 30wt oil at 210F. If you were running an oil cooler and could keep temps down to 220 or so and keep your bearing clearances in spec then a lighter oil would work just as well but free up some HP. Thats why the Cup boys can get by running 5w30 or the like.


[This message has been edited by dirtbuster (edited July 06, 2004).]

[This message has been edited by dirtbuster (edited July 06, 2004).]

Raz_900
Member
posted July 06, 2004 02:29 PM
quote:
Originally posted by bigcityracer:
Well now that I find I know nothing about oil again, I have a couple questions.

#1 First number is the weight of the oil and the second is the viscosity?

#2 So would a SAE30 be kind of equal to a make beleive with me here. (SAE30W 30)


Actually they work together to describe the oil. The weight of the oil is a description we use to label an oil as light, medium heavy, 10, 20 , 30 etc.

The 5w, 10w, 20w etc. portion of the rating is how the oil tested at 0 degrees C (32 degrees F). If there isn't a "w" rating, the oil wasn't tested at 0 degrees.

Now the second portion of a multi grade oil or a straight grade oil, that's the test result at 100 degrees C or 212 degrees F. So it could be possible to have a 30w-30 oil, but an SAE 30 oil might not test out as a 30w at 0 degrees. Hope that makes sense.

Viscosity is the actual measuring scale used to determine the grades. Such as 5w, 10w, 50, 60 etc. Each grade has a viscosity range that it must fall into to be called say, a 10w40. Not all 10w40's will test EXACTLY the same, but they have to be in that SAE defined range of viscosity.

Amsoil posts a decent amount of information on their website for each of their oils. http://www.amsoil.com/products/aro.htm if you click through and check say a 5w30, a 10w40 and 20w50 you'll see the higher viscosity readings for the heavier 'weight' oils. I also found this on Shell's website that shows 5w20, 5w30, 10w30, 10w40 and 20w50 all on the same page (if you have Acrobat Reader installed) http://www.shell-lubricants.com/products/pdf/FormulaShellMotorOils.pdf Notice that at 40 degrees C, 5w30 and 10w30 are very close with the 10w30 being a little higher viscosity. Then, at 100 degrees C, they are both almost identical with the 5w30 actually testing with a bit higher viscosity.

Whhewww... now my head hurts.


rrrrick
Member
posted July 06, 2004 03:15 PM
Here is another link explaining the multiweight oil mystery http://www.vtr.org/maintain/oil-overview.html



bigcityracer
Member
posted July 06, 2004 04:22 PM
Thanks guy, I too am at a better understanding on this one.

So my assumption is a straight sae30, sae40 or sae50 would be the recommended?

gonfast
Member
posted July 06, 2004 09:09 PM
guys 20w-50 oil, is always 20 weight oil, hot or cold but has the lubricting capabilites of a 50w oil. Been in the business for years, even when they first developed multi oil


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