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Evening.

Not a great amount has happened my vehicle recently. I have had to grind a bit out of the engine adapter as it was contacting the propshaft.... need to wait and see if I have taken enough out now. I also have my second mot tomorrow! It expired on sunday... not reminder for the garage :-S

I also have entered the LRO modified vehicle of the year competition. So if anyone would like to vote for me (3 times as you are allowed to vote that many for some reason...) you can do so here

http://www.modifiedlro.co.uk/

Not the best photo. Wings have since been painted and the description could have been filled out a bit more but I was busy at the time! Should also have included a link to all my photos but I'm not allowed to change it anymore :-/

Thanks

Jad

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  • 1 year later...

Afternoon,

 

Has been a long time since I have updated this. Not huge amount has changed but I did go laning in Wales this weekend! This happens far too infrequently <_<

Fitted some new tyres before we went. Glad I did as on the old ones I would have had to be dragged through a lot of lanes! However as it was I only got stuck once due to the leaf spring plates.

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Tested out the articulation and was quite impressed for what really is almost standard suspension.

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We also did a bit of wading proving that the engine runs well when soaked in water ;) Although modifications were made before attempting some of the deeper sections....

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Only had one breakage over the weekend which was the windscreen wiper blade spring :blink: When scraping the screen Sunday morning it was a tad on the rusty side so just pinged into 2 parts when asked to move!

I have been having an issue with the engine stalling and immediately restarting for quite a long time. It has been hard to investigate anything as it was largely intermittent sometimes not occurring for weeks and then repeatably happening over and over again :angry: It was having quite the hissy fit this saturday and sunday morning so I decided to prod around. I didnt find anything in particular but disconnecting and reconnecting the EDIS8 appears to have stopped it so am hoping it was just a dodgy connection on that :i-m_so_happy:

Am also having a problem with one of the leaf springs. As in the picture below it is fouling on the chassis creating quite the rattle!

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I have tried moving the spring over by loosening the U-bolts ratcheting the spring over and then torquing the U-bolts but after a short drive it starts to move over and make contact again! Anyone think of any potential solutions?

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Thanks

Jad

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Great to see the old gal is still going strong, it begs the question though.. Now that you've run it for a good while and gotten used to the power.. When will a Turbo find its way into the engine compartment? :P They take boost so well those 1UZ's!

On the leafspring conondrum, I've had this happen several times, its because the outer leaf gets twisted and doesn't return to the straight position. Too cheap spring material I'm afraid. You could turn it round end to end, then the NeXT time you Flex like mad it might end up somewhat straight :) 

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Haha, I still dont drive it enough! I started cycling to work :blink: so my millage has been reduced somewhat and as I have 3 cars. Its hard to give them all the correct amount of love.... Although I am currently planning to sell my economical car (soon) the only volvo 740 manual diesel turbo sun roof model on the roads in the UK :-o (obviously worth a mint) and lpg the landy so it is a little more economical on long runs, and I am soon planning to put the TVR in my garage to rebuild it but as there is a kitchen occupying it till ~mid January that has been delayed somewhat! So I will be left with my winter and summer cars but both V8's :D

Has anyone got any good articles on LPG'ing a landy with megasquirt? I am trying to see if I can do it without the LPG ECU to reduce cost and size of the components being installed. With switchable maps in MS it shouldnt be too hard to switch over from petrol to lpg components?.... I havent found anyone that has done it and written it up yet :(

As for a turbo.... yes It would be pretty awesome/very possible and completely ridiculous to go and double the Hp and Torque with a turbo.... However then i would be committed to uprating everything in the driveline now! If/when things break. I will only replace with uprated components so the car will go in the direction of being able to have more power at some point.... but thats a long way off! Steering, braking and suspension may have to be enhanced as well!

When you say outer spring do you mean the top spring? I am a bit surprised as they are the original springs as far as I am aware. Would have thought they would have been made to a reasonable standard back then.... I will try and turning it around and then find something to go and drive onto :i-m_so_happy:

Thanks Soren

Jad

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LPG with megasquirt... I think there are only really two challenges -injector impedance, and warm up enrichment.

LPG injectors tend to be low impedance, MS is designed to fire high impedance injectors, like most Bosch stuff. So you either need a driver board, or to find some LPG injectors that are in the realms of the normal impedance for petrol injectors. 

I had a quick look, and doesn't seem like there are any new high impedance injectors around, they all seem to be 1.3-3 Ohm, Petrol ones are normally around 9 Ohm, I think. To give yourself a choice, I'd suggest go with a driver board, there are many peeps on here that could help with that.

Second, for the warm up enrichment, LPG needs no WUE, so when you switch to LPG, relay the coolant temp sender to a fixed value resistor equivalent to 88C or normal running temperature.

There's some other talk about it in here, which I just found when looking for something else!: 

 

 

 

 

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If I had the extortionate amount of money it will cost to do now maybe I would...

But having just had a couple of walls knocked out and the kitchen still to go in and carpets/lights that need to be bought etc etc, even the TVR rebuild money is disappearing!  Will that 4.6 ever get rebuilt to be put in?.... :(

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1 hour ago, jad said:

Has anyone got any good articles on LPG'ing a landy with megasquirt? I am trying to see if I can do it without the LPG ECU to reduce cost and size of the components being installed. With switchable maps in MS it shouldnt be too hard to switch over from petrol to lpg components?.... I havent found anyone that has done it and written it up yet :(

I've thought about doing it, and was about to last year, but chickened out because I managed to get my LPG ECU working again :P

You'll need either a driver board or big resistors to bring the impedance up to levels that don't fry the MS ECU. I think from discussing it with Fridge my plan was to go for the big resistors.

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Thanks Bowie,

The 1uz does have high impedance injectors as well annoyingly. Although there are "upgrades" that are low impedance so potentially changing them so that both LPG and petrol injectors are the same could be a route forward. Although potentially a more expensive way.

The engine on the open road tends to run in the 70-80 degree range (Seams a bit low stat is meant to be 82). It is only when going slow on lanes/idling that the temp goes up until the fan cuts in at 95ish.

Those boards looks like an interesting addition to MS and not very expensive. I am running MS2 are they still compatible? Although it sounds like it might be easier to just put resistors in the injector wiring? How big are we talking Elbekko?

Cheers

Jad

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You could run hi-Z EFI injectors with low-Z LPG injectors quite easily, just depends on where you put the boards on the MS output, take the hi-Z output from before the board, and the low-Z from after, you'd have lots of wires coming out the ECU, but that is OK :)

The driver boards should work with any MS kit, it is only really a device that enables high speed switching of a higher current.

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Thanks Bowie,

Am tempted to give it a go without the LPG ECU. MS should be more than capable of tuning it well without compensating for gas temp and pressure. However if LPG is only used when the car is warmed up then it should be a problem at all.

That would be a lot of wires!....

Jad

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That's interesting to hear! Thanks.

I have been told the following by an LPG retailer. Does it sound correct or not? Wouldn't this mean it is not possible to control the LPG injectors with MS?

"all LPG injectors need special driver - they are driven using pick and hold current driver - so unlike petrol injectors they cannot be opened by applying voltage to the connectors. The PWM 10kHz with current limiting is needed in order to not overheat the coils. There are some injectors with relatively high impedance like Matrix but still - the current needs to be controlled in order to not damage the plunger seasl and to protect the coils."

Cheers

jad

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There is soooo much information i do not know how people remember it all! I found the below. If you follow the injectors and fuel supply link it takes you here http://www.megamanual.com/v22manual/minj.htm which looks like a very helpful page if I could understand it 😂

To tune the PWM [pulse width modulation] values for your engine, you need to know what kind of injectors you have- low impedance or high-impedance. If you are running high-impedance injectors (greater than 10 Ohms), then set the PWM time to a number like 25.4, in essence you are disabling the PWM mode. This allows full voltage to the injectors throughout the pulse width.

For low-impedance injectors (less than 3 Ohms), you need to limit the current to avoid overheating the injectors. To do this, there is a period of time that you apply full battery voltage [peak] current, then switch over to a lower current-averaged [hold] current, i.e. peak and hold. Alternatively, you can add resistors in series with the injectors. See the Injectors and Fuel Supply section of the MegaSquirt® manual for more details.

To run low-impedance injectors with the PWM current limit mode, you need to set two parameters - the "PWM Current Limit %" and the "Time Threshold for PWM Mode" - both are on the “Constants†page. The current limit % is the percent duty cycle when the current limit is invoked. The time threshold is the amount of time from when the injector is first opened until the current limit is activated.

High impedance injectors can run on 12 Volts without problems. Low-impedance injectors require some form of current limiting. MegaSquirt® has pulse width modulation to limit the current. You need to set the PWM parameters to match your injectors:

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Looks like the easiest thing to do it treat it as non pwm as with petrol high impedance injectors as below. Please correct me if I am wrong!

 

Injector Resistors

However, instead of the flyback board, you may choose to use resistors in series with your injectors.

Several people reported that resistors do NOT result in significantly longer opening times, or any other troublesome effects, so this is a good solution for many installs. To eliminate PWM altogether, use a 5 to 8 ohm resistor (with a 20 to 25 watt rating) in series with each injector.

If you want to avoid using PWM with your low-impedance injectors, you can use ballast resistors in series with the injectors. You should use one resistor (20-25 Watts) in series with each injector, otherwise the injectors may not all draw the same current, and the failure modes become complicated and difficult to diagnose. As well, you would need a very large resistor to handle more injectors. For example, if you allowed 2 Amps through four 1.2 Ohm injectors wired in parallel (0.3 Ohms total) to one 7 Ohm resistor, the power dissipated would be:

 

P = V * I = 12.5 Volts * 2 amps x 4 injectors = 100 Watts!

If you use resistors that limit injector current to less than 2 amps, you can disable the PWM mode (by setting PWM% to 100%, and time threshold to 25.4msec) and treat the system as high-impedance. To limit the current to under 2 amps, you need:

resistor ohms = (alternator voltage / 2.0 amps) - injector resistance

For example:

resistor ohms = (14.0 volts / 2.0 amps) - 1.2 ohms

=> resistor ohms = 7.0 - 1.2 = 5.8 ohms

You can also use the calculator below. Enter your injector resistance in ohms, your hold current in amps, as well as your injector impedance in ohms, in the form below and press the "Compute resistor" button.

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Oh jeebus, LPG installers and electronics...

facepalm.gif

 

TL;DR: Just buy some resistors.

The longer version:

1. He means "peak-and-hold"

2. Which is how a lot of low-impedance petrol injectors are driven (including by Megasquirt's PWM routine).

3. Yes, PWM is used to "hold" (limit) the coil current but GUESS WHAT, a resistor does that too.

4. The original Flapper EFI uses low-Z injectors + resistors and that worked.

5. Just use resistors. If it doesn't work, you're only down a few quid and can still buy an expensive driver board to complicate your life if you want to.

6. It's as if he's trying to sell you something or discourage you from doing it yourself...

 

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19 hours ago, FridgeFreezer said:

Oh jeebus, LPG installers and electronics...

facepalm.gif

 

TL;DR: Just buy some resistors.

The longer version:

1. He means "peak-and-hold"

2. Which is how a lot of low-impedance petrol injectors are driven (including by Megasquirt's PWM routine).

3. Yes, PWM is used to "hold" (limit) the coil current but GUESS WHAT, a resistor does that too.

4. The original Flapper EFI uses low-Z injectors + resistors and that worked.

5. Just use resistors. If it doesn't work, you're only down a few quid and can still buy an expensive driver board to complicate your life if you want to.

6. It's as if he's trying to sell you something or discourage you from doing it yourself...

 

:D

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  • 8 months later...

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