Well, I just had to chip in on this one. Motor Oils are something that
can be very personal. Like Chevy vs. ford arguments.. so here we go..
A couple of things to remember, and this applies to any engine in any
car. Dry starts, and running. Dry starts are where the engine is being
started after sitting for a long time like a few days. In this situation,
the oil that had been pumped all round the engine, has had time to drain
off and drip off most of the moving parts. This is where the majority of
wear can take place when first starting up. zero pressure, no oil in the
passages, etc. So what you are depending is the oil's Stick-sion
capability. This is something that is not discussed typically in the press
or even on lists like this. It is something that engine builders are aware
of though, especially if they are building High $$$ engines.
Synthetics typically are thinner than their organic relatives. This
allows them to get pumped through the system quickly at cold starts. They
have to rely on their "superior" lubricating properties once the engine is
hot and the synthetic oil is quite thin. Synthetics do not have a good
sticksion ability. they drain off fairly quickly, but get back quickly once
the engine is restarted.
OK...now to what I have used over the years.. I do not use synthetics
in any engine. Not for running, not for assembly, and not for anyone. For
my engines, I want something I know is slippery under pressure, and not just
because of the hydroplaning property of rotational speed on a liquid. Over
the years, I have been exposed to some of the harshest of conditions for
engines. Drag racing, Road racing, Pro Ralley, dirt bikes, road bikes, off
road trucks, and of course commuter cars..oh, and Boat racers. What I
learned was that you wanted the oil to stay on the parts. Period !!!
Synthetics don't do this. Organics do. Almost all of the Hemi (yes, the
big ones..) drag engine builders that I watched or helped used basically
the same assembly lube
What They used, is the same thing I have found to be the most
predictable.. For Assembly, it's a 50/50 mix of Castrol GTX 20/50 and STP
oil additive. in a 50/50 mix, this stuff is very clingy, and thick and will
not drain off the parts you dip. It's better than the molly lube that's a
round.
As for running Oils, I still use the same components, just in a
different ratio. However, because STP is so slippery, I don't use it for
the first 3,000 miles or so in a street car, or for the break in runs on a
race engine, they don't break in soon enough with STP in there in the main
oil. Once ready, it's GTX 20/50 & STP in the standard ratio of ~ 10-12:1
That's 5 or 6 quarts of oil to one pint of STP. I like Castrol, but other
Paraffin based oils as they used to be called are probably just as good.
They are Quaker Sate, Pennzoil, and one other one I can't remember at the
moment. They are stickier than California/Texas, or mid east based oils.
None of the race engines I ever built, broke or blew up. I can't put all of
that success on the oils, but I can say that all of my cars and trucks I
have had over the years, that I have run this combo in, have all gone
150,000 miles plus without one internal part failure, and no engine smoke at
all.
BTW, on the subject of oil pumps on the 215, Always change the pump to the
high volume pump if you have the engine torn down, and follow the
recommendations through the building books for improving the oil journals in
the block and heads. Some of the feeds are pretty small, which reduces the
volume and the available pressure at the far end due to those
restrictions..Open them up, and use the High volume pump. Raising the
bypass pressure is also good. Don't go bizerk though. too much pressure is
not good. 100 psi can actually strip babit material off the rod and main
bearings.I try to go for about 70 lbs at anything above 1,000 rpm. This
keeps the low end at about 45 to 50 at idle where the rotational speed is
not great enough for the hydroplaning property...
Good Luck and HIGH RPM's to all..
Rich
|