> ----------
> From: Michael D. Porter[SMTP:mdporter@rt66.com]
> > <,to replace the Lucas pump with a Bosch model (quite <common
> > swap).>
> >
> > Sure COMMON BUT NOT WITHOUT ITS OWN PROBLEMS. best use the
> priming
> > pump, say a low pressure solid state pump.
>
<What are people in the TSSC saying about Bosch pumps which doesn't
<filter over across the pond? The general assessment I've read is
that
<the Bosch unit is a superior pump. What are the problems associated
with
<that one?
Dunno, I'm not in the TSSC <grin> I'm in the owners club. There was some
kinda thread in the magazine lately that I can try to find. Resulted in
saying that the pump was not necessarily at fault when you have a decent new
unit and a more improved location. There was some comment about rerouting
fuel pipes as well.
>
>
> years and then
> > the electrics will play up as anyone playing with hot Minis will know.
> > Nevertheless this is probably the best solution.
>
<I won't argue about the environmental exposure--in lots of places
in
<this country and in Europe, that is a concern. However, I live in
<southeastern New Mexico, and the elements don't show up that much
around
<here (~30 cm of rainfall/yr). When it does rain, I can't drive the
GT6,
<anyway--it usually floods around here, and that means water starts
<coming in the door sills. (!)
Point taken, over here you'd be probably using your car for about fourty
days a year when you'd only take it out on days when its not going to rain,
raining or threatening to rain. (nah, only joking its not that bad...)
>
> > >
> One of the other things which can be done, which recently <occurs to me,
> is that the return line can be teed into the pump inlet line a <ways
> ahead of the pump inlet. Residual pressure in the return line is
<probably higher than head pressure, anyway. This would also
minimize the
<problem of using a non-PI tank (the PI tank having, as I understand
it,
<a circular baffle built around the tank outlet, to prevent
starvation on
<turns when the tank level is low). The concerns with this method,
of
<course, are two-fold--turbulence interfering with inlet flow, and
fuel
<temperature at the inlet. I think both of those concerns could be
<minimized with sensible design.
Forgot abou tthe dreaded baffles, too bad. Tank welding is not one of my
favourites...may be putting together a lightweight aluminium tank with a
couple of baffles in 'em would be a good idea. I don't think that its an
entirely good idea to feed the returned fuel back as you would want the fuel
as cold as possible and you might induce some turbulent flows as you say.
Also take in mind that there may be air bubbles in the returned fuel which
you don't really want.
>
> > Another comment, I have read prices of reco metering units, which read a
> bit
> > too low for my liking, make sure you look at the unleaded section of the
> > reconditioned units, otherwise the thing just won't run lng enough to
> > justify its price.
>
> I wonder about this. This may be a function of the clearances and
> materials in the Lucas pump, but a similar problem exists in diesel
> injection pumps (and, of course, diesel fuel has never had lead, since
> there is no need).
Well, its a function of materials rather than clearances. It just doesn't
work. Anyway, metering units recon'd for lead free are not much more
expensive than std units so it probably pays to get them done as additives
are not for free either.
> > Next comment is that the cr of injection engines is higher than at least
> the
> > one of late ec engines.
>
> I'm told by at least one original PI owner in this country that
> compression ratio is a factor in proper performance, and that the
> metering curves are adjusted for an engine with approximately 9.5:1
> compression ratio.
>
>
> Cheers, Gernot.
>
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