I've got a 67 Delmont with the high compression 425, looks and runs like it's a recent rebuild. Would like the group's ideas on the good and bad about synthetic oil use in an old big block.

The car will be used occasionally on weekends at most. It's not going to be a racer but when it is driven it won't be babied...

Appreciate your input.

Thanks

 

forget any oil you can get at the parts store. NONE of it has enough zddp in it for cars with flat tappet camshafts anymore.

Buy an "off road rated" racing oil like brad penn or many others. They will have enough zddp/zinc for your valvetrain to live.

For a car that will recieve minimal use, the extra cost for the "GOOD" oil will likley not even be noticeable since you won't change it often... but if your cam goes flat because of using modern crappy oil, you'll pay a lot more.

my $.02

 

If you're going to only drive is sparingly then don't waste your money on synthetic. For a daily driver synthetic would be a good choice as you only change it once a year. However, in my opinion, not to sound like the ING guy, on a car used only on nice days here and there buy the dino oil..."and save your money." Also what Ben /\ said.

 

Check this out!
http://www.reginaantiqueauto.ca/Oil/keith_ansell.htm

 

Interesting reading.

 

Better reading:

http://www.widman.biz/uploads/Corvair_oil.pdf

From SlantSixDan on another board: Repeating the misunderstandings about the reduction of ZDDP, even in greater detail, does not make it true. But the advice to spend time on BITOG is good. One can learn a great deal by perusing the used-oil analyses (UOA) of various oils used in engines with flat tappets.

Another myth that's got a lot of old-car hobbyists whipped into a baseless frenzy. The current oil certification tests still include flat-tappet engines, and the old Zinc- and Phosphorus-based EP additives have been replaced by others with equal or greater performance. The rumors of flat-tappet engines being shredded by current oils are just that: rumors. They arise out of guesses and assumptions.

sb

 

Shell Rotella, Chevron Delo 400 and other 15-40 diesel oils that meet CI4+ specs (and preferably do not meet CJ spec) have a lot of ZDDP and work well.

 

http://www.chevelles.com/forums/showthread.php?t=128203

More reading... with quite a bit of research to back it up. This guy really became obsessed with it.

There is a lot of info here, you might want to FF to the most recent posts- hes been researching and updating that thread for several years.