chevy1500z71

iv always thought synthetic was a notch above regular oil, but im starting to think its not all its cracked up to be, maybe its not better for EVERY aplication. why is it that you cant break in a flat tappet cam on anything then regular dyno oil? that sort of says something to me, if synthetic lubricated so much better then why cant you use it for the first 5,000 miles on a flat tappet cam break in period? im starting to think that synthetic is an oil better used in roller engines. im thinking maybe regular oil is more of a high pressure lubricant that can withstand the high pressure points of a flat tappet cam better then synthetic could. synthetic could and more than likely is still a better oil, but maybe not in a flat tappet motor... what are your guys thoughts?

Codename 47

iTrader: (4)

On flat tappet motors you should run an oil with zinc and phosphorus additives.

Several years ago the oil companies were required to remove a large amount of zinc and phosphorus from there street car oils.

Flat tappet cams still need it. Diesel oils still contain the needed zinc and phosphorus.

A lot of guys by me run and recommend Schaeffer Oils.
http://www.schaefferoil.com/

Regal105

synthetic oil is so good at preventing wear that your engine eg: bearings, cams, rings, wont break in properly that's why traditional oil is preferred, then you switch out for synthetic to keep your engine at it's best for a very long time

chevy1500z71

but synthetic doesnt have as much zinc and phosphorus additives as mentioned above, so whats the deal? what is the need for zinc and phosphorus additives, what exactly makes these additives ideal for use with flat tappet cams?

Codename 47

iTrader: (4)

Prevents flat lobeing your cam. Phosphorus and Zinc and lubricants. All cars today are roller applications which is why they don't have much phosphorus and zinc in oil anymore.

chevy1500z71

so the question is, which is the lesser of the 2 evils, synthetic is better but doesn't have the proper additives, i can get dyno oil with the proper additives... but its still dyno oil and not a synthetic.

i understand fully now, everything will wear in nicely on a regular oil becasue synthetic is to good at preventing wear which is necessary for break in.

also, in my mind, the thicker the oil, the better. im in Florida so i can get away with whatever i want. im thinking 10w40 would just be extra protection vs the normal 5w30, or is this just a misconception, is there something that thin oil is better at? i would think that thicker oil also helps prevent excessive blow by and this motor will have a blower so i like that idea. but i could be way off, just how my mind thinks of it.

Codename 47

iTrader: (4)

A lot of guys will run 20w50. I have for the past 2 summers. I will be going thinner this summer though.

Run the thinnest oil you can while still maintaining good oil pressure. Thick oil robs power. In fact, a reputable local guy claimed he's seen a ~10 hp gain on several different engines on the dyno. *shrug*

I'll point you to this thread I started up just recently, which is how I know some of your questions. It's about 3 pages, and the more technical talk starts on page 2 I believe. Skim it over, it's good stuff.

http://www.wisconsinstreetdominators...ad.php?t=12865

chevy1500z71

you know, the motors going to make power either way. im much more concerned with just having a bullet proof tough setup than worrying about 5hp. ill probably end up with 10w40. i always tend to run thicker when i can, i run 20w50 in my atv when it calls for 10w-40. id rather have extra protection then an extra measley 10hp on a motor that should make power in the 500hp range anyway. theres better ways to make power then skimp on oil when your trying to make a motor as reliable as possible.

ill read through that thread. thanks.

chevy1500z71

so is rotella t considered a diesel oil becasue i noticed there is a regular rotella t and one that is in a blue bottle that says for diesels on it.

Apeiron

Sure it does.

five7kid

iTrader: (14)

You don't use synthetic for cam break-in because the lobe slips too easily by the lifter and doesn't rotate it. However, if you use petroleum for the break-in and get that spin established, you won't have a problem after that when you switch to synthetic.

Synthetic has higher film and shear strength than petroleum, the two main properties involved with the sliding of the lobe on the lifter. In the long run, it will protect better than petroleum.

However, even the good stuff benefits from the zinc and phosphorus additives. So, after cam break-in, use a synthetic with the CI-4+ diesel rating and SL gasoline rating.

The misinformation out there about oils defies belief.

And, of course, this is a discussion that has already occurred on this Board. Seems to come up about once a month.

Codename 47

iTrader: (4)

Maybe you should throw it in a sticky. Seems like a good thing to read about it. Make it a short one paragraph sticky.

Greg