"Synthetic oil is a relatively recent development..." Say whaaaaaaa? Did you
literally, "dig up the book", as in your backyard? ;-) Maybe it's just me, but
I don't consider synthetic oil a recent development in the year 2000... Even in
racing I don't think it's that new.
On that same note, some may think, but most of us don't, have race setup
engines. I'm no expert but I thought true race engines are setup to run at a
specific RPM and temperature. Hence, they can get away with running a specific
weight oil, like 30, 40 or 50 weight (I really dunno what works best in a race
engine). Not a range of oil viscosity like 10w-30 or such...
For your average work-a-day motor a range of viscosity is critical... I suspect
a day-in, day-out commute would kill a thoroughbred race motor.
I could be wrong, but I think we are mixing apples and oranges here.
Tom
<snip>
I expected to drum up some interest w/that so I dug up the book. Here's what it
says:
On page 164 under a section called "SYNTHETIC OIL"
"Synthetic oil is a relatively recent development, especially in its application
to racing engines. It has been tested, and for most applications, it doesn't
seem to harm the engine. However, it also doesn't offer any advantages if the
viscosityis kept constant. Most synthetic oils are thinner than standard oils.
Also if the engine already has scuffing problems (valve tips, etc.) synthetic
oils wouldn't be recommended based on our testing because of their lack of
sulfur. Lack of sulfur can be counteracted by additives. Refer to your service
manual for specific recommendations. If our engine build-up recommendations are
followed, you should not have a scuffing problem in the engine."
Their engine build-up recommendations include a very tight piston-to-wall cleara
nce per the magnum spec. Also, I understand that at least the 360 motors are
prone to scuffing in the lower portion of the cylinder bores. My Challenger's
360 had bad scuffing in this location.
I wonder if this has anything to do with the magnum engines using Hypereutectic
pistons (do they??). I know that the magnum engines piston to cylinder wall
clearances are much smaller than most older engines. The spec says 2
thousandths I believe. I just ordered a set of KB hyper's for my Challenger
motor rebuild - when I get them back from the machine shop - I'll check to see
what the instructions say - I seem to recall a warning about those particular
clearances and about a special anti-scuff coating. Maybe the lack of sulfur
does something to this coating???
Anyone know for sure?
Latr,
Shane
ps: Remember folks - I'm just the messenger 8-)
-- '96 IndyRam w/lots of mods (mine) '96 IndyRam w/lots of options (wifes) - also a numbered (#142) "Track Truck" '74 Triple-Black Dodge Challenger Rallye 360 home-brew EFI R&D vehicle '68 Black Corvette Convertible 427 (For Sale)
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