babbah

I have read many post stating that the Diesel oil like Delo have more Zinc Additive (ZDDP) than the conventional Oils. I have used Valvoline Racing Oil 20-50 in my Big Block for decades.
My Question is which oil has more Zinc presently - Delo400 or Valvoline Racing 20-50?

buns

Much good info at the link below:



http://systems-engineering-associates.com/



For some reason, unknown to me, I can't link directly to the PDF articles, so you will have to do it manually. Click on the link above, it will take you here:




Then click where I show with the arrow, it will take you here:





There are 3 articles, click on these shown by the arrow and box.

Frankie the Fink

Buy any oil you want and dump one bottle of this in the crankcase on each oil change:
http://www.zddplus.com/purchase_sixpack.htm

That's what I do on my solid lifter 283/270HP

sub006

With Mobil 1 and Castrol Syntec, among others, giving you a fair shot at up to 500,000-mile engine life nowadays, I question the need for ANY additive in normal driving.

That said, once an engine starts to lose pressure, compression and/or mileage, I have found that Lucas Oil Supplement can restore original performance for up to 100,000 additional miles.

Frankie the Fink

That 'fair shot' is for a modern engine...not the old muscle car engine with things like solid lifters and different metal composition. The zinc component of oil was reduced greatly to save catalytic converters in modern cars. The run of the mill oil now (even leading synthetics) don't have what our cars need. There are many threads on this in the archives on this forum.

lib

I have a 63 SB that was newly re-built. The block, crank, and heads were serviced and re-used. All bearings, seals, roller cam, rods, pistons+rings, valve train w/hyd. lifters, hardened valve seats,etc. are new. Does this issue w/Zinc have to do with the design of the motor, original pieces inside the motor (solid lifters) or is it the materials that the parts are made from?

Vetterodder

It mainly has to do with our flat tappet cams. It's not an issue with modern engines with roller cams (or with older engines that have been converted to roller). Even the diesel oils now have less zinc than they used to.

Bob Schaefer

The bottom line is to buy the oil spec not the brand. The "CI-4" spec oil (now slowly diminishing in availability) has slightly more than the newest "CJ-4" spec. However both are better spec oils than our cars lived with for most of their lives and both are sufficient for cam lubrication. Just don't use an oil for spark ignition engines: SM, SL, etc....as Vetterodder said that's a nono for flat tappet cams.

lib - you didn't mention whether you've fired up you newly rebuilt engine or not, but if not the word is that GM has resurrected the engine oil supplement p/n 88862586...just whats needed for insuring lubrication for that first start. Try to MINIMIZE running below 2000 rpm (including cranking time).

Bob