Keith Wheeler wrote:
>
> At 11:26 PM 8/10/98 -0400, Chris Chandler wrote:
> >....
> >Since I'm going to be replacing the oil pump, are the "high flow" ones
> >worth it? ....
>
> Barney Gaylord wrote:
>
> >In a word, no. (I am now putting on my asbestos suit.)
>
> Yep, one of those things that a lot of folks (of the armchair
> variety) will yell and scream about, but a "high flow" pump
> is not a good investment.
Comment... If the NORMAL oil pump has the relief valve open at , say,
75psi with excess oil being passed back to the sump....a 'high flow'
pump will just dump MORE oil back to the sump. So I agree a bigger pump
is a waste of money, UNLESS you open out all the internal oil passages,
and up the pressure relief....but then you can get the oil actually
'boring' away the bearing surfaces....
( The 1798cc 'B' oil pump is deeper than the 1498/1622cc engines anyway,
to cope with the extra 2 main bearings...which leaves the 18G & 18GA
engines with their overworked 3 main bearings in a pickle !!)
>
> I didn't catch what car was being discussed, and I can only
> speak from autocrossing experience with a 'B, but for the
> money the best oil system mod to an LBC is some sort
> of oil sump baffling. At 19 I learned that the hard way
> when hard cornering forces = no oil pressure
Comment.....the XPAG engine, ( in the TD, TF, YA, etc, ) had serious
problems with just this. MG made the sump bigger after engines number
TD2 14948 and SC2 17383, ( just incase any 'T' types are reading this,)
increasing the sump from 9 pints to 10 1/2 pints capacity. As this was
done by making the sump longer at the FRONT, on braking hard you could
run dry as the oil all stacked up. Only a few engine previous to this, (
SC 16729, and TD 7576,) the oil pick up had been centralised due to
RIGHT hand bends losing oil pressure, the pick up was on the left!!
Neil.
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