Re: alfa-digest V7 #658

[bearbvd@domain.elided (Greg Hermann)]

>In a message dated 4/23/99 7:51:26 AM Eastern Daylight Time,
>owner-alfa-digest@domain.elided writes:
>
><<  Is the 5-50 too
> thin and really just a winter oil? Thanks bob Brooks
>>>
>
>Bob,
>The oil engineers warn about using an oil that covers more than 30 points in
>a high revving engine.  The viscosity enhancers are very long chain polymers
>that tend to break down through the mechanical shearing of the oil at high
>rpm, leaving you with a very low viscosity base stock .  I'd stay with the
>20-50.

This concern is VERY true for mineral (dinny) based motor oils, not so true
for synthetics--which is, I believe, what he asked about. Synthetics do not
NEED the long chain viscosity extenders--because their temperature
viscosity characteristics are inherent in the synthetic base stock.

Greg
>										
>					Bill
>								

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