Oil Change
The only justification I can see for not running an oil with >= 1,000 ppm ZDDP in a classic C3 is cost. Does anyone have another reason NOT to?
So simply ask yourself: Is my classic Corvette engine worth an extra $25 or so every 3,000 miles? How many folks drive their C2/C3 more than 3,000-6,000 miles/year?
So...is all this angst really over $25 - $50/year?
The only justification I can see for not running an oil with >= 1,000 ppm ZDDP in a classic C3 is cost. Does anyone have another reason NOT to?
So simply ask yourself: Is my classic Corvette engine worth an extra $25 or so every 3,000 miles? How many folks drive their C2/C3 more than 3,000-6,000 miles/year?
So...is all this angst really over $25 - $50/year?
I run Valvoline racing, change it at 3,000 miles, and drive it 7 days a week, 52 weeks a year. Perhaps more than anyone here.
I would also not hesitate to pour in joe blow oil if I was out in the sticks.
I would not waste money on ZDDP additives, nor would I waste money on "designer" oils, such as Royal P***, or Joe G***.
I use joe blow ATF, GM rear fluid with Posi add, and plain old green Prestone.
Oh, and the 81 burns regular, and on trips with others, I wait at the gas staion while they fill up over and over./. At least I have the A/C on while I wait.
The Best of Corvette for Corvette Enthusiasts
Every catcon on a classic C3 on the planet is junk if it's still in place regardless, given that it would have spent the first 20+ years of its life running oil with 1,500 ppm ZDDP.
So I'll stand by the statement that ZDDP has zero impact on emissions - i.e. use of oil with 1,000+ ZDDP will not increase the emissions on a classic C2/C3.
It's interesting that you say it's not true...at the same time noting that you use oil with well over 1,500 ppm ZDDP and stating that it hasn't affected your emissions.

Last edited by billla; Jul 22, 2012 at 04:59 PM.
However, that does not dimenish the facts. As the engine wears, the Cat WILL be affected.
A 30+ year old cat that has been running 1,500+ ppm ZDDP for most of it's operating life and is junk at this point will experience higher emissions running an oil with...1,000 - 1,500 ppm ZDDP? Nope.
Anyone else subject to smog with old cats want to chime in here?
Or that a GEN I with *no cat* will have higher emissions? Nope.
Or that a new cat running 1,500+ ppm ZDDP will experience higher emissions....even though your personal experience is that it hasn't so far?
And this is driving it "7 days a week, 52 weeks a year. Perhaps more than anyone here."As an "engine wears" blowby increases with will certainly impact emissions...this is unrelated to the amount of ZDDP in the oil.
'nuff said - folks can make up their own mind if emissions are a valid reason not to run oil with 1,000+ ppm ZDDP
Last edited by billla; Jul 22, 2012 at 09:18 PM.

















