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Best oil for B20 engine

Valvoline VR-1 racing oil has more ZDDP (zinc) than most engine oils as its designed for older flat tappet engines like the B20. Volvo recommends a multi viscosity oil, either 10W-30, 20W-40 or 20W-50 for summer driving but I prefer to use straight 30W.
 
hiperfauto said:
Valvoline VR-1 racing oil has more ZDDP (zinc) than most engine oils as its designed for older flat tappet engines like the B20. Volvo recommends a multi viscosity oil, either 10W-30, 20W-40 or 20W-50 for summer driving but I prefer to use straight 30W.
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Curious if Volvo says multi weight why do you prefer straight 30W?
Just about to help the boy with his tired B20 oil change.

Thanks
 
Straight 30W is actually recommended for temperatures above 90?F.

It's my opinion (and mine alone) that 30W clings to the camshaft better than multi viscosity oils and provides better protection until oil begins to circulate.
 
Nothing wrong with synthetic at all, but it's somewhat wasted on an engine like the B20 which doesn't really have any unusual features that synthetic would work well for (i.e. a turbo that tries to coke the oil on hot shutoff).

As already mentioned, though, those lifters and cam lobes really need more ZDDP than modern car engine oil provides, because a little oil burning could otherwise foul a catalytic converter. So you could either add a little bit to whatever oil you do use (like a good synthetic) or buy oil that has more ZDDP in it already, like the VR-1, or some diesel engine oils (since diesels don't have the same sort of cat).

I just get a bottle of Lucas engine break-in additive, which is mostly ZDDP, and add part of the bottle in with each oil change:
10063-tb-zincenginebreakinoil-16oz.jpg


Keep those cam lobes happy!

PS: Another odd thing about the B18/20 - is that the cam lobes really aren't directly oiled in any good way. Oil is pumped up into the head to the rockers under pressure, and then it drips down back into the sump via the lifter gallery, where it oils the lifters (which do not get any pressure oil feeds), and then presumably down past them and sort of onto the cam lobes?

I really think that the bulk of the oiling the cam lobes get is from crank windage - all the oil droplets flying around down in the bottom of the crankcase after being flung off of the rod bearings.
 
Love these motor oil discussions.

A few comments.

As I understand it, racing oils have higher zinc and phosphorus that these older engines need but lack many other additives that extend the life of oil, since racing oils are intended to be changed after a few hundred miles, or less.

Indiscriminately adding ZDDP can result in too high a level which is actually disastrous for lifters and cams.

Zinc and phosphorus levels in the 1100-1300 ppm range are what?s needed. For conventional oil I use Napa All Fleet 15W-40, and synthetic, Mobil 1 15W-50, which both have the appropriate levels of Zinc and Phosphorous.

Synthetic oil can also do a good job of cleaning up internal deposits, but you may experience some increased drips and leaks.
 
I use Swepco 306 in my International Scout and that engine reminds me of the B20. I'll probably use it in my rebuilt B20 but for now it leaks and burns it at a rate where I am not putting that type of gold in there. :)
 
Mobil1 for modern engines or anything with a Turbo.

15W-40 Diesel of older or air-cooled. Usually Shell Rotella.

Swepco products are wonderful, but hard to get and expensive here. Best trans fluid for manuals period. Blue gold!
 
c1800 has got it right. There are lots of people who believe modern oils have low levels of zinc. Not true, there is enough zinc content to keep almost any engine happy in most available oils, flat tappet or not.
 
c1800 said:
Love these motor oil discussions.

A few comments.

As I understand it, racing oils have higher zinc and phosphorus that these older engines need but lack many other additives that extend the life of oil, since racing oils are intended to be changed after a few hundred miles, or less.

Indiscriminately adding ZDDP can result in too high a level which is actually disastrous for lifters and cams.

Zinc and phosphorus levels in the 1100-1300 ppm range are what’s needed. For conventional oil I use Napa All Fleet 15W-40, and synthetic, Mobil 1 15W-50, which both have the appropriate levels of Zinc and Phosphorous.

Synthetic oil can also do a good job of cleaning up internal deposits, but you may experience some increased drips and leaks.
Click to expand...

Agree. Sufficient Zinc and Phos in a CJ-4/SM 15W40 for this engine..
 
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