Pjd131

Hi guys. I hate to do this but I have an oil question. I have read many threads on the subject and a few technical documents but still searching for an answer. I realize this may be a beaten horse, but here it goes anyway. I have a 911 with a 3.2 and a catalytic converter. I want to retain the cat. The car has about 80k miles. Is there an oil out there that has sufficient zinc and phosphorous to protect the engine but not too much that it will destroy the cat. Don't hate me for asking the question. Thanks guys.

Amber Gramps

I was beaten into compliance just months ago by the RL brain trust. VR1 it is.

http://www.pepboys.com/product/detai...nlyStore=false

LexVan

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Reiver

If you use an oil with the proper ZDDP levels it will, eventually, clog up your cat.
What does a rep cat (tons of good used ones around, one in my garage) cost over the cost of worn cams/tappets / top end?

racngrn

I registered as an antique and can run without my cat. It was in excellent shape, so I put on the by-pass and carefully packaged up the original cat. I run Valvoline VR1 and also add some ZDDP additive for good measure. May be overkill, but I sleep better.

Pjd131

Like that idea racngrn. I read up on VR1 and found this in their FAQ at (perhaps others make similar claims??).

http://www.valvoline.com/faqs/motor-oil/racing-oil/

What solutions does Valvoline offer to the zinc issue?
Valvoline offers two solutions to the zinc issue:

Valvoline VR1 Racing Oil: Contains 75% higher zinc than SM motor oil with a balanced additive package designed to work in both racing and street-legal applications. This product will protect older style push-rod and flat tappet engines. Valvoline provides this product in both multi and mono viscosity grades: 20w50, straight 50, 10w30, straight 30, straight 40, and straight 60.

Longer-Lasting Zinc/Phosphorus: Valvoline uses an advanced zinc/phosphorus additive that keeps higher levels of phosphorus in the motor oil where it protects the engine instead of poisoning the catalytic converter. Valvoline is the only brand offering this unique additive across its entire line of passenger car motor oils including SynPower -- the only synthetic oil that offers this additive.

Starbuckslova1

Use brad penn or porsche classic oil

Ed Hughes

Zinc additives are a waste of money. Oil with the proper formulation will suffice.

Also, look at Joe Gibbs Driven. The only high ZDDP oil I know of that may cause issues with cats, is the Mobil 1 V-twin oil.