James, I personally run a bit more pressure than stock, because I do use 6000+
revs. The stock SD1 engine would be hard pressed to turn 6000, due to
restricted intake and a baby cam. As a practical matter, the engine won't pull
much beyond the power peak which is around 5000 in stock form. 7700 is
possible in theory, but only with some serious bottom end work and a valve
train much modified. The heads, which cannot be made to really breathe, might
make it impossible. John
James Nazarian Jr wrote:
> 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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