Et voila se que j'ai trouvé en fuinant ds la faq du site US valvoline concernant la vr1
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.
Which oil has more zinc/ZDDP: VR1 or "Not Street Legal" racing oil?
Valvoline VR1 Racing Oil contains .13 percent of zinc and .12 percent of phosphorus compared to the Valvoline "Not Street Legal" Racing Oil which contains .14 percent of zinc and .13 percent of phosphorus.
Will an additive boost the zinc level?
You can use an additive to increase the zinc level. However, check with your motor oil manufacturer to ensure the additive is compatible with your racing oil.
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