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Discussion Starter · #1 ·
Thought I’d kick off a thread for those of us interested in EV conversion of SY and SZ series.

There have now been several attempts at this, some more succesful than others, but my goal is to try and assemble some resources, and discuss options relating but not limited to drivetrain, brakes and suspension, steering, controls, and the ethics of converting these historic vehicles.

As a starter, here are my own ideas, please feel free to add projects or any thoughts you have

Automotive parking light Wheel Vehicle Car Tire
 

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Is there merit in putting the motor in the original gear-box area, using the prop-shaft and diff, and so keeping the rear end undisturbed? That would mean less work(??) but might need a reduction gear somewhere, but it should fit in the "gear-box" space. It would help to keep the original weight distribution, too. Offered with no practical knowledge of doing such a conversion.

Alan D.
 

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Discussion Starter · #3 · (Edited)
Is there merit in putting the motor in the original gear-box area, using the prop-shaft and diff, and so keeping the rear end undisturbed? That would mean less work(??) but might need a reduction gear somewhere, but it should fit in the "gear-box" space. It would help to keep the original weight distribution, too. Offered with no practical knowledge of doing such a conversion.

Alan D.
I did originally consider that, but dismissed it as the Tesla motor/diff combo is just so much more elegant and overall a LOT lighter than what you propose.

There does not need to be any change to the rear suspension, and the performance is nicely inline with what the chassis supports, ie 1998 Turbo R level.

Weight distribution is about the same as stock.
 

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Interesting project, great website.
You keep the hydraulic brake system with front sphere and rear hydraulic suspension with rear sphere ? You just replace mechanical pumps by hydraulic pumps ?
 

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It is an appealing project if it is reasonably DIY. The electrics and installation don't bother me. The mechanical work might, depending on the scale of machining necessary. In a few years time it might be the only way one could enjoy driving a PMC without a guilty feeling (15 miles per UK gallon and all).

If you make the conversion simple and can reproduce the fittings needed, or someone copies your fittings, I would be in the market. And a few other folk, too?? Keep the hydraulic system as much as possible with a small electric pump - the hydraulic energy needed by the suspension and brakes is quite small. The steering load is considerable, though, so electric steering??

Sorry, I'm only making suggestions. I don't have the bravery to attempt it alone.
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Alan D..
 

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Discussion Starter · #6 ·
Interesting project, great website.
You keep the hydraulic brake system with front sphere and rear hydraulic suspension with rear sphere ? You just replace mechanical pumps by hydraulic pumps ?
Correct.

The trick is finding suitably quiet pumps, or devising a means to silence them.

Some conversions have already solved this for Citroen DS.
 

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Discussion Starter · #8 ·
It is an appealing project if it is reasonably DIY. The electrics and installation don't bother me. The mechanical work might, depending on the scale of machining necessary. In a few years time it might be the only way one could enjoy driving a PMC without a guilty feeling (15 miles per UK gallon and all).

If you make the conversion simple and can reproduce the fittings needed, or someone copies your fittings, I would be in the market. And a few other folk, too?? Keep the hydraulic system as much as possible with a small electric pump - the hydraulic energy needed by the suspension and brakes is quite small. The steering load is considerable, though, so electric steering??

Sorry, I'm only making suggestions. I don't have the bravery to attempt it alone.
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Alan D..
Electric steering would be ideal, but I think the approach that some (e.g. SuperfastMatt for whom I have a great deal of respect) have taken, namely servoing the steering through the steering column, may put too much load on the RR rack.

So may be better to replace the whole rack with an EPS
 

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Citroen DSs have a multi-cylinder pump to serve the whole power system including steering, which takes a lot of effort. The ID series, which were cut down versions of the DS, had a single cylinder pump to run the suspension only, and in emergencies the brakes as well. In all these Citroens - I have owned many and still have two - the greatest, and only significant load on the hydraulics is steering. A pump with a tiny flow-rate will serve the suspension and brakes as long as it produces lots of psi and has an accumulator. Twice.

Alan D.
 

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Discussion Starter · #10 ·
Why quiet? It can be a standard RR pump driven by electric motor with a cam.
Good idea, I think I may have part of an old camshaft I can use somewhere :).

Providing the necessary lubrication for the pump may be a challenge, and I have no idea how powerful the motor would have to be...
 

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Discussion Starter · #11 ·
Citroen DSs have a multi-cylinder pump to serve the whole power system including steering, which takes a lot of effort. The ID series, which were cut down versions of the DS, had a single cylinder pump to run the suspension only, and in emergencies the brakes as well. In all these Citroens - I have owned many and still have two - the greatest, and only significant load on the hydraulics is steering. A pump with a tiny flow-rate will serve the suspension and brakes as long as it produces lots of psi and has an accumulator. Twice.

Alan D.
Good point, and another reason for EPS
 

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Providing the necessary lubrication for the pump may be a challenge, and I have no idea how powerful the motor would have to be...
Approximated power could be calculated. There is needed working pressure, diameter of piston and stroke, and rotation speed of cam ;) Lubrication is easiest part? - cam can flood in oil in sealed housing? Maybe even not in engine oil but LHM+?
 

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Discussion Starter · #13 ·
Approximated power could be calculated. There is needed working pressure, diameter of piston and stroke, and rotation speed of cam ;) Lubrication is easiest part? - cam can flood in oil in sealed housing? Maybe even not in engine oil but LHM+?
Cool, do you happen to know what the equation is?
 

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Yes, I think.
With pressure and surface area of piston you will get a force.
With force and stroke you will get a torque.
With torque and rotation speed you will get a power.
Then you will assume losses (friction mainly) and efficiency, multiply by number of pumps, and it is all. IMHO.
 

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I think it's ethical, if you keep all the old parts safely tucked away somewhere. That way if someone ever wants to switch it all back for a museum piece, they can.
 

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I think it's ethical, if you keep all the old parts safely tucked away somewhere. That way if someone ever wants to switch it all back for a museum piece, they can.
It would never be possible to reverse such an undertaking back to "factory original," AKA, museum piece.

I have a SY2 series car that was originally built for the home market that was converted, ahead of my ownership, from RHD to LHD. Even just doing that involves changes that would be very, very difficult indeed to reverse.

Given that we're talking SY and SZ motorcars, which had production numbers that were huge (by RR standards) the probability that there would be anyone who wouldn't just buy one in original, "unmolested" condition if that's what they want is infinitesimally small.

Also, I'm willing to speak heresy - they're just cars. Owners should feel free to make whatever modifications they wish. They should also be aware of what that does to the car's value in the collector car market for that marque. An EV converted RR holds virtually no value in the RR collector community. It almost certainly does in the classic car market as a whole.
 

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Also, I'm willing to speak heresy - they're just cars. Owners should feel free to make whatever modifications they wish. They should also be aware of what that does to the car's value in the collector car market for that marque. An EV converted RR holds virtually no value in the RR collector community. It almost certainly does in the classic car market as a whole.
I agree, owners should be able to do what they will to their own property. And they are just cars. It's not going to hurt anything to convert one to EV. Quite the opposite, it'll be a vast improvement. If RR always had the option to use electric drive for luxury purposes, I think we all know they would've. It's simply better in every way. That fits their ethos perfectly. So I wouldn't feel the list bit bad about it.
 

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Discussion Starter · #19 ·
How heavy are those batteries vs the V12 engine? How much weight does the whole conversion add, vs the oem equipment?
The batteries weigh about 400kg in total

It’s possible to put 100kg in the fuel tank area, so 300kg vs the weight of the engine , transmission and ancillaries.

The transmission weighs about 100kg.

I dont have any firm numbers for the weight of an L410 (anyone?) but id think it wont be far off 200kg ( a Rover V8 weighs 145kg)

So given you also lose the exhaust, inlet tract and propshaft, the weight should be about the same as stock, as will the weight distribution.
 

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Discussion Starter · #20 ·
It would never be possible to reverse such an undertaking back to "factory original," AKA, museum piece.
Actually that is one of the overarching goals of the project.

The batteries are abstracted by the battery cages, the drive unit by the motor cradle; the hydraulics remain virtually untouched, as does LV battery system.

Can you think of something specifically that would not be reversible?
 
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