Oil for the fix....

[novadude]

[ Driven Hot Rod and Mobil 1 High Mileage work great.

I think Mobil 1 HM 10W-30 is a great, affordable, "WalMart" oil. With it's ACEA A3/B3 rating and HTHS of 3.5 mPa*s, it should do a nice job of protecting with a reasonable 100 deg C viscosity. Seems like a smart choice for a street / strip engine. I had already settled on this oil for my next oil change, so it's interesting to see it mentioned here along side a boutique oil.

[cjperformance]

How many street/strip guys here are running an oil temp gauge and know exactly what oil temps they see?

[novadude]

How many street/strip guys here are running an oil temp gauge and know exactly what oil temps they see?

Better question.... how does sump temperature even relate to what the oil temp is at the piston-to-wall interface, etc? Not saying that it's not a good data point, but I don't know if it tells the whole story.

[cjperformance]

Sump temp wont directly relate to piston to wall or bearing interface but oil condition on analysis will tell if the oil has been baked as will strip and inspection.
Its pretty natural that certain areas are going to be hotter than the averaged sump temp but if oil temp at the sump is staying in check , clearances are right and tune is correct then chances are that all else oil temp wise is ok.

[Krooser]

Chris...explain the centustoke number to me

Measurement of flow at temperature.

Okay.....

[midnightbluS10]

Never heard of a specific centistoke rating. So how does Valvoline 10W30 Race oil non synthetic rate for hyd. rollers?

I use a mix of 2 qts. VR 20W50 mixed with 4 qts. VR 10W30 during the summer months.

Look up any viscosity specs on oil and it's listed in those specs. You just never noticed it before, I'm guessing.

https://sharena21.springcm.com/Public/D ... 162d889bd1


Shows VR1 20w50 @ 20.5 @100C and 10W30 @ 11.5 @100C.

Start looking at specs for oil. You'll notice it's always been listed with all other specs. You just never new how to use the info so you likely just looked straight over it.

[cjperformance]

I cant handle the way Lake Speed/Driven make everything sound like a 2am infomercial , the web site, charts, vids... screams marketing machine.
Their stuff is good but their approach just turns me off. JMO.
Vis index doesnt even really matter, if you know your temperature range you pick by cst/vis to suit your min and max temp, the SAE rating then is purely a way to know which oil Vis range you want but only withing a particular brand and product line. We've been trained to look at x/xx sae vis range as a packaging choice but not many folk actually understand it, go to an auto parts store and ask the wandering sales staff for an oil that has 189cst@100 & 20sct@212 , its fun!
It really would be great if oil were sold by Vis at 40C_100F / 100C_212F
Eg, from Chris' list, a Driven BR30 5W-30 would be sold as a "63/11" oil. Then a lifter company can say ok we need you to use an oil with less than X@100 & less thanX@212 and Joe Bloggs can go buy that oil no problems.
You could then also simply compare Vis of brands A,B , C etc directly off of the labels. If you want to know vis V's temp outside of this then yeah look up the PDS.

[RCJ]

is there any oils that have the centistokes ratings above 100c. 220f to 240f is a common oil temp and I have completed a race on a wet sump motor at over 300f

[cjperformance]

is there any oils that have the centistokes ratings above 100c. 220f to 240f is a common oil temp and I have completed a race on a wet sump motor at over 300f

Not that I know of but that does not mean much!
You can try these calculators if you know your 100f/212f cst ratings. Handy for higher or lower temp aprox cst ratings.

http://www.nimacltd.co.uk/viscosity-cal ... mperatures

https://wiki.anton-paar.com/en/astm-d34 ... apolation/

P.s. what oil are you using and how does it hold up, do you have it analyzed?

[RCJ]

The high temp was with Castoil 5-50 synthetic on a 600 hp Imca late model.the race went green to checkers on a hammer down track.I changed the oil after the race and ran the motor the rest of the year.THe castroil got hard to find and I switched to 20-50 renegade because it was easy to get.I sent it to a lab once, but I didn't know how the read the results

[naukkis79]

is there any oils that have the centistokes ratings above 100c. 220f to 240f is a common oil temp and I have completed a race on a wet sump motor at over 300f

Every oil has also rated with HTHS viscosity, which is oil centistokes at 150c.

[cjperformance]

is there any oils that have the centistokes ratings above 100c. 220f to 240f is a common oil temp and I have completed a race on a wet sump motor at over 300f

Every oil has also rated with HTHS viscosity, which is oil centistokes at 150c.

Excellent, point but IIRC hths is cP's @150c.!? Not a straight cst comparison but a great indication of what the oil is doing at higher temps.

[ctk30]

I’m guessing this is probably why certain oils make duramaxes have a ticking noise

[smeg]

As someone who has a good knowledge of how hydraulic lifters work, can someone explain to me and everyone else, how changing the oil makes the lifters less noisy? What makes them noisy in the first place? Please give me an explanation how the valve systemin the lifter works well and why it doesn't with different oils, like 20-50 vr's 10-40.

[cjperformance]

As someone who has a good knowledge of how hydraulic lifters work, can someone explain to me and everyone else, how changing the oil makes the lifters less noisy? What makes them noisy in the first place? Please give me an explanation how the valve systemin the lifter works well and why it doesn't with different oils, like 20-50 vr's 10-40.

Basically the lifter hydro part is a bore closed at one end with an oil feed hole in the side with a check valve/ball , a close fitting piston(pushrod cup) with a spring to hold it in its upward position and between the spring and piston is (varies brand to brand) a valve typically a flat disc. Engine oil pressure allows oil to fill the bore below the valve, the spring takes up lash(adjuster part of the mechanism) and the "hydraulic lock" effect of the oil in the bore transfers movement of the lifter body(lobe lift) to the piston/pushrod cup.
Basically depending on clearances, valve type and oil feed position the hydraulic valving will prefer either a thicker or thinner oil.
Loose clearances will allow thin oil to flow thru easily so will prefer a thick oil that bleeds out slower to hold the piston in the correct position as the lobe lifts.
Tight clearances will prefer a thin oil to allow the oil to enter the bore/piston quickly while the lifter is on the base circle which allows the lifter to 'recover' from the small ammount of piston recession (read as lift loss) thru the lobe cycle.
Tight clearances are better for accuracy but suffer with thick oils that can not flow as quickly therefore the piston does not get to fully recover(take up lash) so the lifter becomes noisey.
Loose clearances are more forgiving to a point but not as accurate and suffer from excess bleed off with high valve spring pressures and lift rates.
Thats the basics.