64SilverbluePhx

Our '64 has a crate motor that on the manual I received with the car, is handwritten "Installed 3/04". GM Performance 350/333hp Part No. 12496968 Vortec. What oil would be best to run out here in the high summer temps? Currently running synthetic 5W/30 Mobil 1, doing an oil change so your thoughts would be appreciated. Thanks in advance!

reno stallion

Joe Gibbs racing oil. If it has a roller cam use the synthetic if not conventional

AZDoug

15W-40 Rotella T for about anywhere in the country.

I wouldn't run 5/30 in any gen 1 small block. Its not a Toyota.

Doug

reno stallion

I don't think rotella T has enough zinc in it. but if its a roller it wouldn't matter

64SilverbluePhx

Thanks for the input reno stallion and AZDoug! My bad, it is 10W 30 that was in it. Motor is flat tappets. How much zinc does it need in the oil? Can I go from synthetic back to conventional?

reno stallion

Yes you can go back to conventional. If you run the Joe Gibbs the zinc is in it already. Or you can use any good oil and Lucas makes a zinc additive that will also work

64SilverbluePhx

reno stallion what weight do you run? I looked up Joe Gibbs and they have several weights... Though I didn't see a 15W-40... thanks again both of you for the help!

GTOguy

I agree. And just say NO to racing oil for an engine that is driven on the street. Racing oil is meant to be run hard and dumped after the event. It has no additive package for sitting in a crankcase for months and for keeping acids and corrosives at bay. I run Rotella in all my old cars, and have for the past 12-15 years or so, when the ZDDP was removed in most part from conventional motor oils. You could run the Brad Penn or Hemmings boutique oils with great results, if you like paying $8-$12 per quart. I can buy a whole gallon of Rotella for $12 on sale..........

reno stallion

I would not run a flat tappet cam with an oil without zinc. Dose it say military storage protection

reno stallion

Don't buy cheap oil made for diesel pickups

C.T.

I've used the Rotella 15W 40 for years with good results. '57 270.

GTOguy

Why not? It's excellent oil and proven effective in older flat-tappet engines for hundreds of thousands of miles. Much better than racing oil, which would be my last choice on a street driven car.

AZDoug

And diesels have very high loads on bearings and cylinder walls due to the extreme high compression. It isn't cheap oil, it is relatively inexpensive oil compared to specialty stuff.
Doug

GTOguy

Yep. And the diesel engines running this well-engineered oil typically run 500,000 miles between overhauls, too.

capevettes

Run the Rotella 15W 40. It has plenty of ZDDP for a flat tappet motor. I've run it for years in my old Vettes with zero issues. Forget the boutique and "racing" oils. They only lighten your wallet.

reno stallion

Not quite sure what you mean about racing oil did you not read the jug far superior to oils with out zinc. Has every thing that cheap oil has and then some. Don't get me wrong I use rottela in my dodge diesel but not my hot rods. Number one cause of cam failure lack of zinc in todays common oils.They took out the good additives some time ago. Probably cause cancer

SWCDuke

Search for threads started by me. Download the oil article pdf, read it thoroughly, and you will be able to make an intelligent decision based on facts, not opinions or misinformation.

Duke

cv67

I think by racing oil he means non detergent?
There is NO perfect oil that will make a huge difference.
i run a wix filter and the cheapest oil for my DD (lsx) i can find. 185k and runs just fine. USed Mobil 1 for the first 60k it was just wasted money obviously. If machining assy and parts quality is good, you arent revving the thing to the moon cold most engines can last indefinitely.
An expensive high rpm deal,upgrade some.

Wiht flat tappet cams having shear strength is more important than just a "slippery" oil. See comment above about bearing load.

AZDoug

You seem to be non person in the search engine.

Even clicking right on your name shows 0 threads and only four posts.
Doug

GTOguy

What I mean is that true racing oil has NO ADDITIVE PACKAGE for street-use conditions: long periods of idling (hydrocarbon contamination), High temps, cold temps, constant cold start/hot start cycles, in the crankcase for months at a time, etc. Additive packages that neutralize oxidation and corrosion and can hold up to contamination are necessary in a street engine. In a racing engine, with racing oil, the oil is meant to protect the moving metal parts in the engine during the event. This oil is usually dumped out after a weekend, or a race. It was never meant to stay in your crankcase for 4-6-12 months as a regular oil. If you want to use it, go for it. Me---- working in street driven engines for the past 40 years as a professional--- I simply know better.