Mobil 1 oil weight

[Ameer Antar]

FWIW, I checked the records on my rebuild and it looks like it has .0027
clearance on the mains and .0024 on the rods. I think the journals were
actually within spec before the rebuild, but I had them grind it down anyway
since it was cheap enough to start with close to new clearances. The pistons
have .0036. No idea about the cam though. I know it was in spec before the
rebuild, but I didn't save that info and didn't have them worry about it at the
machine shop since there are no replaceable bearings for the cam.
 
What do the V8's run?


-------------------- Original Message --------------------
From: Al Streicher [streichea001 at hawaii.rr.com]
To: Ameer Antar [antar at comcast.net], john at westcoastgarage.net
Cc: Quattro List [quattro at audifans.com]
Date: 5/1/07 4:37:50 PM
Subject: Re: Mobil 1 oil weight

 > Ameer,
> Although the bearing are new is not the point, it's the clearance between
> said bearings and the crank or camshaft. If the clearance is say.002"-.003",
> then I would say use a 30 weight oil. The viscosity needs to match the
> clearance. If the makeup is a thick oil, say 40-60 weight, you'll need more
> clearance to allow the molecules to squeeze into the gap. Plus, as mentioned
> before, what is the make up of the oil passages, narrow or wide? As the
> enigne is worn in, you might have to increase the viscosity.
> I can only speak to older Chevy engines, that I have rebuilt many, they use
> very tight clearances and always recommended 10W-30. In a typical V8, most
> of the oil was pushed up to flood the valve area and the cam.
>
> If you do not get valve noise upon startup and the oil temp is normal for
> that engine, then stay with "Dino" oil or a blend. IMHO
>
> Al
> ----- Original Message -----
> From: "Ameer Antar" [antar at comcast.net]
> To: [john at westcoastgarage.net]
> Cc: "Quattro List" [quattro at audifans.com]
> Sent: Tuesday, May 01, 2007 5:04 AM
> Subject: Re: Mobil 1 oil weight
>
>
> >I agree that 0w40 is too extreme for my old car, but I was thinking of
> >sticking
> > with 10w30. I based this off the fact that the S6 has a similar engine
> > design
> > and has a similar oil grade chart to mine. So if A=B and B=C, then A=C,
> > right?
> > Keep in mind this is a rebuilt motor, so it's not like I'm running on 22+
> > yr
> > old bearings.
> >
> > -Ameer
> >
> SNIP