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Rover 820 - MEMS & AEB

Posted: Sat Jul 28, 2012 1:13 am
by markocosic
Following on from the (unfinished, but about to be worked on simultaneously) Daimler Super V8, kid bro' thought that LPG on his Rover 820 hatch would be a useful addition.

I've bought a secondhand kit from a P38 Range Rover: King/AEB ECU, MagicJet injectors, Tomasetto Artic reducer, and a 77L 4-hole Stako donut tank with JIC fill and the recessed bayonet filler. The vehicle met a sticky end not long after the kit was fitted and the autogas-lpg warranty stickers are dated 03/2012 - cheaper kits were available but this seemed like a good balance between being inexpensive and worn out. (230 quid)

An unexpected win - it came with a Valtek Type 74 shutoff solenoid that we need for the SuperV8. I'll be swapping the valves between the 77L and the 96L tanks.

The plan is to chop the spare wheel well out, fit a flat boot floor, then fit the tank UNDER the boot floor. This will save an enormous bunch of mucking about with the vent hoses/false floors and whatnot, and the filler will be towbar mounted on a 50 cm JIC hose so no visible bodywork faff.

8 mm copper feed pipe (I bought a huge roll for the SuperV8) under the car, but I'll run the wiring internally this time.

Reducer is a lovely little thing compared with the KME Golds. Built in filter and shutoff solenoid. This gets bulkhead mounted, and will feed a single 12 mm filter that's mounted to a bracket on the gearbox (to reduce injector noise travelling through the bulkhead). That runs to the injector rail hung on the rear of the intake manifold - much like this:

but lower, as on the 800 there's gallons of space between the engine and bulkhead. The MagicJet injectors are teeny tiny compared with the HANA injectors I used on the SuperV*. (can see why Simon recommended them now, even if they do look like they were made in China not the Czech Republic)

AEB025 picks up on one of the intake manifold bolts, a 6 mm stub on the injector rail, and a 6 mm stub helpfully provided on the intake manifold!

ECU location TBC. Probably in the engine bay on the bulkhead, but might fit near the petrol ECU and the battery.

Mapping TBC. The MEMS cars have narrowband oxygen sensors, the output of which is standard as far as I know but the structure of the sensor is slightly oddball (universals don't work well). MEMS also does some nasty micro-injections for acceleration enrichment that we'll have to deal with. Else the car does have an OBD socket (it's a last of last of/run out model; 1999 registered but post 1996 model year) though I've o idea what info is available over it at the moment. (probably OBD not OBD II?)

Anybody ever done a T-Series MEMS Rover and remember which settings you used? (820, 420, 220, turbocharged 620, Discovery MPi, Morgan Plus4 etc)

Valves are LPG-proof at least - if anything their lives should be better on LPG. On early M-Series engines the valveseats were from billet unobtanium to handle unleaded fuel. On these later T-Series engines they added more oil-cooling to reduce valve temps and pre-ignition, but this run the exhaust valves too cool and carbon buildup on the stems caused them to stick if used by grandad about town. (fine if thraped about by a 17 year old though) Later engines had looser exhaust valves guides and carbon break valves. LPG will run them hotter with less carbon so all should be well. Failing that, replacement engines cost less than flashlube kits... :wink:

Cold starting on LPG is of interest. These engines are state-of-the-ark and I used to run a "manual choke" on mine in the Land-Rover using a changeover relay and 220 ohm resistor for the coolant temperature sender. Tell the ECU the engine was "hot" long before it actually was hot and saving a bunch of fuel. (it is an iron-block engine that took an age to get up to temperature compared with modern stuff) How does LPG respond to this type of treatment? Do you need cold start enrichment at all? Might switching in the resistance that tells the petrol ECU that the engine is hot work?

Re: Rover 820 - MEMS & AEB

Posted: Sat Jul 28, 2012 9:15 am
by Tubbs
Ive done literally hunderds of them on a mixer. Very popualr taxi ! What year are we talking ? Or shape and engine v6 honda or k ? There is a muliplug on the bulkhead, thick red wire with a black trace ? Injector live, it wont k light as i remember. I cant honestly remember if they are full or part group. I dont think the mems was a fully sequential system. I may be wrong though, i never had to find out. Just relay the injector pos out and off you go. Never had one go bang. And they managed millions of miles between them.
But fitting an injection system ? I suppose i would nowadays too....the king ecu will have all the settings to take care of micro injection. Thats not a problem. Could have an obd socket i suppose, wether you can get an actual fuel trim value out of it is another matter. Im sure all the pin data is on the older autodata cd. I will have a look when i get to work later. Other than that its all pretty strightforward, loads of room in the bay.

Re: Rover 820 - MEMS & AEB

Posted: Sat Jul 28, 2012 9:47 am
by Tubbs
Where you at with the v8 then ?

Re: Rover 820 - MEMS & AEB

Posted: Sat Jul 28, 2012 10:20 am
by markocosic
I've got 2 weeks on both.

The V8 needs the supercharger removing and the nozzles in the manifold moving - plus a bunch of suspension work. I've got hold of another pair of inlet manifolds to play with. Current plan is to make "straws" external to the manifold. Drill and tap M10x1; screw a barrel nut for 6 mm dia pipe into that; bend 6 mm solid pipe around the ba$&ard tight manifold and solder it into the barrel nut to act as the nozzle; 6 mm hose from the other end of it to the injector. Waiting on the LPG/suspension parts for that though, so the plan is to gas kid bro's Rover this weekend whilst he tears all the subframes off the Jaguar/generally gets the heavy/dirty/upside down jobs, then I'll switch to LPGing the V8 again.

She's a 1999 model; very last of production. T-Series engine (the 2.0 four pot - it's an iron blocked development of the old M/O/B Series, not the all alloy K-Series even though from the top it looks similar)

Three wires feed the injector harness, so it'll be part sequential. Have found a wiring diagram on RAVE and it looks pretty straightforward - just trying to find the neatest positions for parts at the minute.

Good news on the AEB front - you can set the King 568 ECU to 34568 cylinders in the software, so I don't have to muck about telling it that the 4-pot is a 5+ pot. Fitting the injection system as the old mixer systems are all old and knackered by now. They weren't that good to begin with - I used to have a T-Series in my Land-Rover and was looking to LPG that back in the day, but drove a few 820s on mixers and they were like jumping into a carburetor car. Noticeable loss of torque at idle; didn't like the throttle being wide open at low rpms; easily 10% down on power too.

The 6 month old kit was 230. Already have the 8 mm copper for the under-car run; need a little 12 and 6 mm LPG hose and a little wire; saved us 50 quid on the Valtek 74 for the V8 so owes us perhaps 200. Could pick up a shagged mixer system with a naff cylinder tank for 50, but fixing it would take more money and the economy difference will soon recoup the extra 100 anyhow?

Re: Rover 820 - MEMS & AEB

Posted: Sat Jul 28, 2012 10:34 am
by Tubbs
I agree with you. But taxi drivers where never bothered about power loss ! Just money saving ! So its a half group injection system then ? Should be pretty strightforward.

Re: Rover 820 - MEMS & AEB

Posted: Sat Jul 28, 2012 10:59 am
by markocosic
A typo in the AEB manual: ... attachment

Page 22 talks about the O2 wires, and lists the same colours (grey-black, violet-black) for both O2 sensors. This is wrong. Grey and violet is bank 1. Grey-black and violet-black is bank 2.

Re: Rover 820 - MEMS & AEB

Posted: Sat Jul 28, 2012 1:21 pm
by markocosic
Injector cuts:

Neatest if done on the injector sub-harness.

NB is ignition live for the injectors. Tap the WR into this.

YG is Inj 1&4. YU is Inj 2&3. Cut these. Blue and Yellow connect to injectors 1&4; blue/black and yellow/black connect to the feed for injectors 1&4. Red and Green connect to injectors 2&3; red/black and green/black to the feed for injectors 2&3.

O2 sensor wire is UY; rpm feed is WY or YB.

Pick up a few male/female "Bosch" or "Super seal" type connections for these taps as it makes the system easier to fit/car easier to service. Also use these for the gas and water temperature senders; shutoff valves etc, as King harness doesn't come with any connectors for these.

Re: Rover 820 - MEMS & AEB

Posted: Sat Jul 28, 2012 10:51 pm
by mat_fenwick
Ross has mentioned previously that LPG doesn't require the same amount of cold weather enrichment as petrol - giving too long gas injector times if changeover temp. too low.

Re: Rover 820 - MEMS & AEB

Posted: Sun Jul 29, 2012 10:00 am
by rossko
It's evident that cold running enrichment is not required for LPG, from the example of old-tech mixer systems: they just start and run from cold with no such sophistication.
(A primer mechanism is sometimes used for start only, just to get gas into the manifold before the presence of any vacuum - not the same as enrichment)

I guess it's a consequence of having a naturally vapour fuel at start-up temps, as opposed to a liquid.

The petrol ECU could be fooled about cold running with a CHT resistor. That could be automated with a little ingenuity to only work when LPG selected, and even then to switch to the 'real' sensor after a time.

Some engines are easier to start with slave LPG injection than others - whatever startup strategy the petrol ECU uses (extra injections etc.) is faithfully copied onto the gas and would be difficult to prevent.
Gas-only starts are generally not advised, partly due to that and partly because if the petrol system never gets any exercise it just ain't gonna work when you need it to.

It will all go wrong at sub-arctic temperatures, but should be good down to -20C or so.

Re: Rover 820 - MEMS & AEB

Posted: Mon Jul 30, 2012 12:38 am
by markocosic
A lot of those old mixer systems ran rich as sin at all times mind. :lol:

Wiring fitted; water tees made; injectors/filter/vapouriser/ECU bracketry made; manifold removed/tapped/refitted. This thing is a genuine pleasure to work on compared with that bloody Jaguar!

Let's leave it starting on petrol but switch to gas early, and gas in the fully hot/closed loop flavour.

I've teed into the coolant temperature sensor (CTS) wires, and brought this out to a Bosch type 2-pin plug. Plugged into this as a "mk1 kludge" is a relay. When you power the relay it conencts a 220 ohm resistor across the CTS wires. Low enough to say "fully hot" but high enough resistance not to trigger "dead short" fault code. At present the coils of this relay sit in parallel with the shut-off solenoid on the vapouriser, so when the LPG is engaged the car's ECU will be spoofed into fully hot mode. No harm leaving it there, and the dash gauge is fed from a seperate sender so the driver still knows true temperature. Can be unplugged in polar bear weather.

LPG ECU can decide when to make the swap. Set changeover to 30C vapouriser water temperature and/or 30 seconds and it should always start on petrol then switch to the gas (and bring in that relay) pretty quickly. Changeover could be messy if it turns the liquid on first then takes it's time about bringing in the gas, as you'd be running on petrol without cold start enrichment for a few seconds. Probably ok for kid brother's car but not mother's car. Will see what the King ECU is set to do anyhow. :)

Re: Rover 820 - MEMS & AEB

Posted: Mon Jul 30, 2012 10:51 am
by mat_fenwick
You'll have the option to open solenoids in advance, so I'd leave that unticked...

Re: Rover 820 - MEMS & AEB

Posted: Mon Jul 30, 2012 11:49 pm
by markocosic
Thanks! Under the "sensors" menu - loving the Italian logic. :lol:

Set to say 25C reducer temperature. Changeover during acceleration, say 1750 rpm so that it doesn't stumble and die whilst waiting at a junction or whatnot; 0 overlap time. Give it 0 delay before changing to gas. Don't turn electro-valves on in advance. Don't do a sequential changeover either; do all four pots at once.

This should start the engine and let it idle on petrol indefinitely, then switch to the LPG as soon as the revs hit 1750 and the coolant is vaguely warm? As soon as the switch happens it'll be on the "hot" map from the car ECU.

4 cylinders. Wasted spark coils for rpm feed. Injectors are wired in pairs for part-group/semi-sequential.

Question on the semi-sequential injection: The software gives three options. Sequantial; MJ Sequential; Full Group.

Which do I use for part-group? Sequential or MJ Sequential?

The micro-injection fudge is under "Modify carb" menu.

Is there an option for reverting to petrol at low gas pressure/what is the default behaviour with a King/AEB system?

Re: Rover 820 - MEMS & AEB

Posted: Tue Jul 31, 2012 9:07 am
by markocosic
Aha, the Zavioli manual is better translated and annotated:

Choose "sequential" for the semi-sequential engine. Gas changeover may still be a problem:
In general, the GAS control unit activates the GAS solenoid valves for about 1 second before
switching from PETROL to GAS. This allows enough time for the gas tubes to fill up. If the default
time of 1 second is not enough and the vehicle turns off when switching from one type of fuel to the
other, you can activate this option. The GAS valves will be opened at least 5 seconds before the
system switches to GAS, thus allowing for higher levels of fuel in the GAS tubes. If the option is
not activated, a warning will be displayed on the screen to remind the user not to stop the PETROL
So it'll hiccup for 1 second on changeover as it switched to hot map on petrol for 1 sec and then to gas. Wonder if AEB can change this - will fire their tech support a question.

Re: Rover 820 - MEMS & AEB

Posted: Tue Jul 31, 2012 9:11 am
by markocosic
The "extra-injection cutting" option on the King software is greyed out. I'm assuming that I'll need this for the MEMS micro-injections. Is it just on mine that it is greyed out, or is it on all King versions of the AEB ECU?

Re: Rover 820 - MEMS & AEB

Posted: Tue Jul 31, 2012 9:37 am
by Gilbertd
markocosic wrote:Is there an option for reverting to petrol at low gas pressure/what is the default behaviour with a King/AEB system?
The default is reverting to petrol at low gas pressure, that's how it detects that you are running out.
markocosic wrote:So it'll hiccup for 1 second on changeover as it switched to hot map on petrol for 1 sec and then to gas. Wonder if AEB can change this - will fire their tech support a question.
What's it got to do with AEB? You are the one that is messing around with the petrol map, not them. It MAY hiccup for a second (or more depending on how long it takes for the gas pressure to come up) as it switches and you have a cold(ish) engine running on a hot petrol map before switching to gas. Where it still may run a bit rough until the engine is up to temperature. Why not just leave things as they are and set the changeover temperature a bit higher? Or fit a lambda feedback (so it doesn't run rich) single point, which you've already been told will work well on these engines, and run on gas from stone cold? Why do you insist on thinking you know better than the people that spent millions developing these systems? Your Jag would probably be finished and running perfectly if you had taken advice from someone that fits systems to this engine regularly rather than going about it your own way.

If the intention is to get it to use as little petrol as possible, why not plumb the vaporiser in series with the heater (assuming it doesn't control temperature with a flow valve and is a free flow system) so all the available heat passes through it rather than only half of it as it has a choice of routes to take. Rather than switch your relay to simulate a fully hot engine with the solenoid feed, why not switch the relay when it cuts the petrol injector pulses (a 555 timer circuit with one of the gas injector pulses taken to the reset pin, or use a 555 to put a 1 second delay in the relay being switch in). You are into experimentation beyond what the kit has been designed to do so it's no good complaining to AEB that their ECU doesn't do what you want it to do as you are the only person that is trying to do it. There's a number of ways of achieving what you want but it is up to you to come up with the solution.

Why do you insist on thinking you know better than the people that spent millions developing these systems? Your Jag would probably be finished and running perfectly if you had taken advice from someone that fits systems to this engine regularly rather than going about it your own way. You botched that one, why are you trying to do the same with this one?

Re: Rover 820 - MEMS & AEB

Posted: Tue Jul 31, 2012 9:48 am
by mat_fenwick
Gilbertd wrote:You botched that one, why are you trying to do the same with this one?
I think that's a bit harsh. However, my advice would be to see IF there's a problem before worrying about it - a good job 100% completed is better than a perfect job that never gets finished…I know from experience! :oops:

If the changeover is set to happen on deceleration then any 1 sec hiccup is unlikely to be noticeable.

Re: Rover 820 - MEMS & AEB

Posted: Tue Jul 31, 2012 10:15 am
by rossko
markocosic wrote:So it'll hiccup for 1 second on changeover
If you want to delay some relay action for a second or two from the "gas on" event, you can use AEB's timing relay

Re: Rover 820 - MEMS & AEB

Posted: Wed Aug 01, 2012 12:50 am
by markocosic
Simples! That's elegant rossko, thanks. I think the emulators that I bought for the Jag but didn't use have an adjustable timer in them; will rig one of those up as a coolant temperature sender emulator.

More than one second would be no problem at all; probably a good thing even. Petrol cold-map; LPG cold-map; MPG hot-map.

I wouldn't worry about Gilbertd Matt. He's one of those people who have just two ways of doing things (their way and the wrong way) and gets mighty frustrated when the world chooses otherwise, but sometimes he has helpful links and things to say too.

The objective is to delete the cold-start and warmup enrichment on an engine that takes a lifetime to warm up. (the Stag ECU has an option for just this called "impoverishment of the cold engine" and for some vehicles they even sell coolant temperature sender emulators pre-built. AEB systems don't have this; probably a reflection on the Polish vs Italian climates...)

Improving the reducer warmup time won't solve this problem. You would still be running with cold start enrichment as the engine coolant temperature sensor is still cool. Even if you did want to improve reducer warmup time, plumbing it in series with the heater on an 800 would be a dumb idea. (water flow to the heater matrix is controlled by the climate control system and isn't constant - teeing in is the correct way to feed from these)

Single point systems work badly on these engines. The intakes are designed for multipoint injection. (responsiveness suffers with big plenums, long runners, and single point injection unless you design the intake manifold for single point injection) The mixer rings kill top end power. Economy is poor too. Ok at idle and very light cruise if you have the lambda feedback, but to get the thing to run without flatspots elsewhere it's running rich as sin. Tried several back in the day (2002/2003) and came to the conclusion that these systems were an improvement on a pair of knackered strombergs* but nasty on anything else.

*many Land-Rover types tried to persuade me that a nice 3.9 V8 on gas was the way forward. I listened, ignored the experts, and decided that a much smaller turboed engine was the way forward...



200 horses, flat torque curve from 2,000 through 5,500 rpm. All mounted well behind the front axle so 1500 kg (with cage) 53:47 front-rear. 25 mpg on petrol. Or 25 mpg on 120 RON gunwash thinners at 2/3rds the cost. (mostly toluene; feed this only to the early engines with the metal fuel rails) Loved the 4.7 diffs and 205/80 tyres too, so no need to change the gearing. Ran a 1.410 high range and 3.32 low range on the transfer box, so crawled beautifully in low box.

Most of the RV8 owners were surprised. The naysayers were miffed. Some of the more enlightened ones broke out into a huge grin though. "Where did you get that short bellhousing? I'd like one of these in my comp safari machine..." (the Discovery MPi has a huge long bellhousing; 1700 O-Series LDV has a stubby one that'll all bolt up to the later M-Series/T-Series or L-Series diesel)

Kept screwing the boost up until I got bored with the back axle having a short and unpleasant life. Final incarnation was 10.5:1 compression with the early (stronger) M-Series bottom end from a naturally aspirated car and heavily skimmed head, with 14.5 psi boost thrown in on top. Efficient and quick, and with the 120 RON gunwash thinners didn't pink either.

Or I could stick a V8 in; but where's the fun in that. :lol:

1400 or 1600 turbo next; as decent RWD ones become available.

Re: Rover 820 - MEMS & AEB

Posted: Thu Aug 02, 2012 12:56 am
by markocosic
Made a start on the tank fitting this afternoon... :lol:


Sod working around the confines of the car; make space then bracket to suit. It's getting a 77L (650x270) tank as that what was in the kit. 96L (720x270) would go too. Boot floor rises 40 mm, so there'll be a tank frame from 40x40x2 mm box, tied into the structure with 1.6 mm sheet, with some 1.2 mm over the tank as the final boot floor. OE spare wheel well (shear panel) was 0.8 mm.

Re: Rover 820 - MEMS & AEB

Posted: Sun Aug 05, 2012 12:50 am
by markocosic
Tank frame/boot floor fitted and painted. Stako tanks have four lugs on them. One might assume that these are at 0/90/180/270 degrees. One would assume wrong; these seem to be welded on by a drunkard and won't fit if you make your frame exact. :lol:

Spaces to the left and right of the tank frame will be filled with 50 mm "spaceboard" foam with a piece of 6 mm ply on top. The foam cuts nicely with a router on low speed to make trays for your hi viz, poncho, gloves, jump leads, tow rope, spare bulbs etc. Throw a fabric that drapes well (old builder's sacks) over the foam and it'll keep indefinitely.




Lesjofors still make the (factory) police spec rear springs for the the old 827 vitesse hatchbacks. These fit all 800s and are 40 quid a pair brand new. We've ordered a pair as it's a workhorse with a towbar that's often loaded to the rafters and could use them even without the LPG. May have to remove the rear anti-roll bar if it's too tail-happy when empty as they're significantly uprated. (+2.5 mm on coil diameter IIRC)