Ok, I am now officially ignorant. What the heck is PAO oil? And why is it
supposed to be better than just plain old oil...
mayf, off planet in Pahrump
----- Original Message -----
From: "Bryan Savage" <b.a.savage@earthlink.net>
To: "List Land Speed" <land-speed@Autox.Team.Net>
Sent: Wednesday, December 08, 2004 10:53 AM
Subject: Re: What's in your crankcase?
> This is just my opinion....
> I don't see why a roller bearing 4 stroke needs any more oil than a
> roller bearing 2 stroke in the bottom end.
> I'd like to know the reasons the NASCAR folks running Mobil Oil have
> gone to a 0W-30 PAO oil.
> I know of one case where the rod bearings were taken out before
> the 1 at World Finals. 20-50 synthetic oil, no warm-up and very cold.
> The biggest killer of bearings is air.
>
> Bryan
>
>
> Stephen F. Doherty wrote:
>
> > If I may branch off and address viscosity:
> >
> > One of the comments that is commonly made about Rollie Free
> > is that he ran a very low viscosity oil, like 10 wt (or
> > maybe less?), and one also hears about racers pre-heating
> > the oil, to avoid running the engine for a time to get
> > the oil up to temp. I also suspect Rollie wasn't concerned
> > about getting hundreds of flat out miles from the engine,
> > just enough miles for that year's meet.
> >
> > This raises a few questions.
> >
> > How significant of a power loss difference is there between
> > running lighter or heavier weight oil?
> > The Vincent, having roller bearings on the crank and relying
> > on oil flow, not pressure, is this a more favorable environment
> > to run a lighter oil, ie can a plain bearing motor cope with
> > such a light wt oil?
> >
> > What weight oil would you say (guess?) is the 'norm' for land
> > speed racers, either overall or separating out bikes from cars?
> >
> > For whatever reason, I had this perception that all, or most,
> > land speed racers were running as light a weight oil they could,
> > and this comment of running 50 wt stood out.
> >
> > SFD
|