0-30wt Synthetic Oil

[cudabob496]

Well, I use to run 10-40wt regular oil, then 10-30wt syn oil, then 5-30wt, but just did an oil change and am
running 0wt-30 Mobil 1 synthetic in my 496 big block (stroked 440). Also added Engine Restore to fill scratches
in cylinder walls.

Figuring we get 90% of engine wear at startup, not much other oil is gonna flow faster at startup.  And, the bottle says gaurantees same
protection as 10-30wt.

I think most or a lot of the engines as the Masters Engine Building challenge run 0-20wt.

Have taken it out twice. Oil pressure is almost immediate at startup. Car seems to run fine.

Main goal is for engine to last as long as possible, before I have to rebuild.

I'm sure this post will get some discussion.

PS run synthetic oil in my lawn mower, and its going on 18 years! Also run it in the Cuda tranny
and rear end.

[Changin Gears]

I'm an old school guy, run 15-40, 20-50.  Never really wanted to get the last few hp(or mpg) by running the thinner oil.

My thinking has always been the thin oil would run off the camshaft and cylinder walls after the engine was shut off leaving less protection during start up.

I've always run synthetic in my mower also, seemed like nothing was harder on an oil than an air cooled engine running full-throttle in the middle of summer.

[cudabob496]

I've read that the worry about synthetic oil not sticking to metal was just a myth that came up
when synthetics came out about 20 or so years ago. Most all the high performance cars sold
in the world recommend and use synthetic oil. Many of the fighter planes in WWII used synthetic oils.

[Chryco Psycho]

Syn is good oil , the only downside is to get approx 4-5000 miles on the engine before switching to it to allow the rings to seat in .
 Any 0 weight oil has a negative mental connotation , 0 + nothing , no protection , but not true 0 weight oils are fine 

[Moparal]

My partner puts 0 wt royal purple in my dana on my 72 cuda race car.  I was skeptical, but he helped me build it and it still works great

[Changin Gears]

I've read that the worry about synthetic oil not sticking to metal was just a myth that came up
when synthetics came out about 20 or so years ago.

Never heard that one before.

[cudabob496]

if you put synthetics in engine, tranny, rearend, you should add roughly 20 hp to the rear tires, depending on engine power output.
I burped a lifter once, and went down the road for a mile or two with no oil pressure. I think the synthetic oil saved my engine. Regular
oil will break down around 450 degrees, but synthetics don't till over 700 degrees I think.

Something like 30 or 40% of engine power is needed just to overcome internal engine friction.

[cudabob496]

My partner puts 0 wt royal purple in my dana on my 72 cuda race car.  I was skeptical, but he helped me build it and it still works great

hmmm, the synthetic in my 8 and 3/4 rear is still 70-90w!

I agree, having the number zero in the title, implies no protection, which is not true.
Just means lower viscosity.

[Strawdawg]

I have never seen a scientific test that demonstrated that thin oil ran off internal parts any faster than thicker oil but I admit to have seen some magic machines sitting on store counters that claimed to prove this.  Oil companies and car companies don't seem to believe it.

I have seen a number of dyno tests that show improved hp from the first run on synthetic oil but the numbers evened out on subsequent runs when comparing equivalent weights of syn vs conventional.

I think one has to be careful comparing Engine Masters or Nascar race engines to street cars as engine life is projected to be much shorter on the first two as they are purpose built.  I am not sure that Engine Restore has ever filled in a scratch in a cylinder wall either, for that matter

As long as the oil pressure is satisfactory, I would run the lightest weight oil that meets my definition of satisfactory   We can get away with lighter weights these days as we build engines a bit more precisely than they did in the 'sixties and the oils are much better than they used to be with regard to thermal breakdown, etc.

[cudabob496]

I have never seen a scientific test that demonstrated that thin oil ran off internal parts any faster than thicker oil but I admit to have seen some magic machines sitting on store counters that claimed to prove this.  Oil companies and car companies don't seem to believe it.

I have seen a number of dyno tests that show improved hp from the first run on synthetic oil but the numbers evened out on subsequent runs when comparing equivalent weights of syn vs conventional.

I think one has to be careful comparing Engine Masters or Nascar race engines to street cars as engine life is projected to be much shorter on the first two as they are purpose built.  I am not sure that Engine Restore has ever filled in a scratch in a cylinder wall either, for that matter

As long as the oil pressure is satisfactory, I would run the lightest weight oil that meets my definition of satisfactory   We can get away with lighter weights these days as we build engines a bit more precisely than they did in the 'sixties and the oils are much better than they used to be with regard to thermal breakdown, etc.

Surprised the hp numbers would even out.  Synthetics simply lubricate better, and about 30% to 40% of all the power an engine makes is taken up in just
overcoming internal friction (ie pushing those pistons up and down the cylinders).  One way to prove that synthetics lubricate better is to survey how long engines last, whether on synthetic or regular oil. All the data I've seen shows a synthetic oil engine lasts longer. Which seems to be the case with all the cars I've owned.

[RCCDrew]

How do flat tappet cams like 0 weight oil?

[cudabob496]

How do flat tappet cams like 0 weight oil?

dont see a problem. Zero weight just means less viscous than 5wt, but its still oil that protects
the metal. Put some between your fingers, and its still slippery as snot! And synthetic zero weight
provides better lubrication. It just has to have essential additives for flat tappets (like zinc).

[wiging19]

dont see a problem. Zero weight just means less viscous than 5wt, but its still oil that protects
the metal. Put some between your fingers, and its still slippery as snot! And synthetic zero weight
provides better lubrication. It just has to have essential additives for flat tappets (like zinc).

What synthetic oil has zinc in it.  I've ready several threads that say even with regular oil only a few contain zinc any more.  So you have to add zinc.  Is that true for Synthetic?

[sadil340]

I use Rotella T 15w-40 in my rebuilt 340 and if the engine sits for more than a few days my lifters clatter like a diesel for a few seconds. So much for traditional oil staying on the cam better. I will probably switch to a 0w- synthetic after I get 5000 miles on the engine.

The only down side to synthetic oil that I know of is it can slip by gaskets easier than dinosaur oil and make a little more mess. 

[cudabob496]

I use Rotella T 15w-40 in my rebuilt 340 and if the engine sits for more than a few days my lifters clatter like a diesel for a few seconds. So much for traditional oil staying on the cam better. I will probably switch to a 0w- synthetic after I get 5000 miles on the engine.

The only down side to synthetic oil that I know of is it can slip by gaskets easier than dinosaur oil and make a little more mess. 

That clatter is due to no oil getting there for a few seconds.  Lotta wear goin on there.  Synthetic will flow there a lot quicker. Your rings should be broken in after 1500 miles. I'd go to synthetic.