how does all this relate to the old rule of thumb 10#s per 1k rpm? It
would seem if an engine only makes 40#s then you shouldn't rev over 4k?
But the mechanical redline (piston speed assuming no valve float) doesn't
happen until 7700 rpm
James Nazarian
71 B Roadster
71 BGT
63 Buick 215
"Aerodynamics are for people who cannot build engines"
Enzo Ferrari
----------
> From: Susan and John Roper <vscjohn@huntnet.net>
> To: Larry Hoy <larryhoy@prodigy.net>
> Cc: Glen Wilson <rstca@hemmings.com>; V8 Rover List
<buick-rover-v8@autox.team.net>
> Subject: Re: Rover V8 Oil Pressure
> Date: Saturday, September 02, 2000 1:13 PM
>
> Actually, 8-10# at idle at operating temp would be quite acceptable.
Rovers, SD1
> and later(Ihave no recent experience with pre-SD1 stuff) will not make
30# at idle
> unless there is something unusual in the oiling system. A 3.5L TR8
engine that I
> recently sold would make 25# at cold idle, stock 70k engine, but at
normal temp it
> was down to 10 as expected. Be cautious about using high viscosity oils.
The gear
> drive has known limits and attempts to make the system produce high
pressures can
> lead to failure. The system is designed to move volume, not make
pressure. My
> experience with bottom ends for the race car carefully assembled with
components
> properly machined, flow restrictors in the heads, relieved passages in
the block,
> and a pressure regulator on the relief valve resulted in some very high
cold idle
> pressures, which dropped below 20# at temp. John
>
> Larry Hoy wrote:
>
> > Lets see if I can sort this out. This gets confusing so hang on.
> >
> > Glen Wilson writes:
> >
> > >Larry,
> > >
> > >Pardon me if I'm jumping into this thread in the middle and have
missed
> > something, but 8-10 psi oil pressure at idle doesn't sound normal to
me.
> >
> > Glen wrote the above because I posted the following question.
> >
> > >John, your reply was regarding the 8-10 pound oil pressure at idle,
what would
> > be the typical pressure at driving speeds (2000-3000 rpm)?
> >
> > I asked the question because John had posted the following answer and I
thought
> > he was responding to the idle oil pressure:
> >
> > >Your pressure is about what is to be expected. The Rover motor does
not make
> > high pressures.
> >
> > John was replying because David Brown stated:
> >
> > >I recently installed an oil gauge and discovered that my NEW (well,
17K miles
> > now) 4.6 block is only getting 8-10 psi at idle.
> >
> > And he further stated:
> >
> > >my cruise pressure is around 35-40 psi, so not too bad.
> > >
> > >What can I do to beef up the 3.5L oil pump?
> >
> > Whew, did you figure that out? I did my research and found the *1961
Buick*
> > engine should be running about 33 lbs. at 2500 rpm (thanks to others
who
> > responded and gave me similar numbers). But I did not find out any
info on idle
> > pressure. However the brief time my engine was running it ran around
the 30
> > mark at idle. Seems to me that 8-10 lbs at idle is low.
> >
> > Larry Hoy
>
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