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Running Jolt/Squirt on gas


Landrover17H
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Running Jolt/Squirt on gas

it can be done, however has anyone actually done this? V8 or Series?

I run a 2.5 with a BLOS and AEB Leonardo to control Lambda in closed-loop, and frankly it's pretty good. How do I know for sure you ask? I've a wideband gauge, and it stays pretty much smack-on, most of the time. I'm sure there's gains to be had but does anyone know, aside from doing it 'because we can' what can be expected? It's not EFI, yet I can say  don't knock a BLOS and a Leonardo.

But has anyone done a 'gas' with  Jolt/Squirt?

Lambda Wideband.png

Edited by Landrover17H
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Jolt is spark only so doesn't know or care what your fuelling is.

Squirt doesn't care what fuel it's injecting - as I understand it the LPG injection setup is basically the same sensors etc. just that gas goes in rather than petrol so, again, MS really won't care.

Does your system have a wideband sensor fitted or just the gauge? :mellow:

And does it actually vary the AFR with engine load or is it just hunting a fixed AFR across the board?

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Have jolted and BLOS log carb on another vehicle before, ran well, and solved the V8 electrical gremlins in one swoop.

Not sure anyone has solved the LPG thing on MS yet, part of the trouble is the injector current/impedance, I believe.

 

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2 hours ago, Bowie69 said:

Not sure anyone has solved the LPG thing on MS yet, part of the trouble is the injector current/impedance, I believe.

Not sure what you mean there, MS can run most injectors :huh:

Might be trickier if you wanted to have staged injection with a set of High-Z petrol injectors and a set of Low-Z LPG injectors using able switching but even that shouldn't be insurmountable.

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58 minutes ago, Bowie69 said:

I forget the complication, but there was one....

Having been interested in running injected LPG at one stage, I know of one complication.
It centres around lubrication of the injectors. As I understand it the fuel passing though the injector acts as a lubricant; while diesel is good, and petrol is OK, liquid LPG is not.
Obviously it is a problem that is overcome with CNG, but no doubt at considerable cost, well beyond the scope of backyard amateurs.

Regards.

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49 minutes ago, FridgeFreezer said:

I'd hope the LPG injectors that are part of an LPG injection kit are up to the job of injecting LPG :huh:

I'd hope so too; they must be a development from after my involvement, which thinking back, was getting on for 10 years ago 🙂

Regards

 

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Ok, I remember part of the problem -lpg doesn't need any warm up mixture enrichment, and there was no way to do that in the software as while you had fuel table switching, there was only one warm up table. Probably same for ASE and AE as well as other things I haven't thought of yet.

WUE wasn't too hard to fix, just relay in a fixed resistor when you switch fuel.

The others, more problematic, but in real life may not matter.

I think injector dead time was something else too? LPG injectors having long dead times Vs the petrol ones which are pretty short.

There may be more, but that was what my brain spurted out earlier when pondering stuff.

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For those that don’t know a BLOS works like an SU carb.
I suppose it could be said, my set-up is the gas-equivalent of adding closed-loop Lambda control to an engine running an SU carburettor.

Best I explain. I’ve a single-point stepper-motor controlled gas system. Closed-loop, it uses a narrow-band/ O2 sensor to control a stepper motor, which in turn meters gas-supply. The hey-day for this sort of thing was best part of 15-20 years back.   They have limitations, yet converting from petrol and carbs, nothing gets simpler. Range Rovers were favourite using an AEB Leonardo ECU.
It's a lowest common denominator system,  installing a Lambda is as difficult as it gets. More usually the stepper would feed a cooker-ring.

In my case the stepper feeds a BLOS. I'm sure I could do away with the BLOS, and substitute a plain cooker-ring, but I'm guessing the  BLOS gives the stepper less work to do. It works well.  Back in the day BLOS even made a ECU metered version of their own (see diag).
I've also a second sensor, wide-band it feeds a gauge. This wide-band has no link with the stepper set-up. The WB is there purely to feed a WB gauge. It acts as, if you like, an audit to the AEB Leonardo. As a result I’m able to verify the ECU controlled stepper is doing it’s job.
It works. I have to say, it’s very good. I’m not sure if going multi-point via MS will follow the law of diminishing returns, but I’d like to try. This is the root of my question.

Gas injectors? CNG or LPG, neither fuel carries too much lubrication, I've not seen a distinction. They're gas injectors, some do both liquid and gaseous fuels, but if specc'ed for gas, they'll inject gas, and deal with both gases equally. Lubrication etc is not really an issue. However I think many have different impedances, and running gas, may have to stay open longer. Those piggy-back systems can handle this sort of thing, seems madness to piggy-back onto MJ though?

 

BLOS Evolution.png

Edited by Landrover17H
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Could MJ run something like this? Only I've heap of 'em laying about at the moment.

Bosch Natural-gas injector NGI2

 

NGI2 210LBS HIGH IMPEDANCE BOSCH FUEL INJECTOR 2200cc 0280158821

BOSCH HIGH IMPEDANCE FUEL INJECTOR
0 280 158 821 MADE IN GERMANY! 220LBS/HR
Features:


These injectors flow 2200 cc/min at 43.5 PSI (3 BAR) and are fully compatible with alternate fuels and alcohol. These new injectors from Bosch represent the next generation of high flow injector technology with fast response times, excellent flow pattern and compact design.

These injectors very well suited to turbocharged and supercharged applications that see high fuel system pressures. .

 

Specifications:


Coil Resistance: 9.1 Ohms / Low Impedance
Dead Time: 0.45ms at 14 volts
Static Flow Rate @ 43.5 PSI ( 300kPa ) w/Gas: 2200 cc/min = 210 lb/hr
Static Flow Rate @ 58 PSI ( 400kPa ) w/Gas: 2550 cc/min = 240 lb/hr

Connector: Denso / Sumitomo
Injector Length: O-Ring to O-Ring: 1.5. / 37.5 mm
Injector Body Diameter: 16mm
O-Ring: 14.5mm Viton

Acceptable Fuels: Gas/Petrol, alcohol/methanol, E85, CNG

 

Body Design: Composite plastic w/internal filter
Electrical connector type: Bosch Jetronic
Body Design: composite plastic w/internal filter
Electrical connector type: Denso (Sumitomo)
Injector type: Saturated, EV14


===================================

 

 

 

 

NG12 Data Sheet.pdf

NG12.png

Edited by Landrover17H
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I've had 3 setups running MS2 + LPG on mine so far - original was a cooker ring and a closed loop system with a stepper for the gas. Second was the same but with a BLOS carb, which was a lot better than the cooker ring. For both of these, MS was wired so when on gas the injection table was zero'd and some extra advance was added in.

Since putting the 4.6 in I've swapped to multi-point with an AEB gas ECU running in parallel to the MS2 - not done much setup as it's not been used since the lockdown and the engine is only just run in, but the plan is to let the gas ECU control the switchover, have a second spark table on the MS with more gas friendly advance and maybe tweak the second fuel table to be tuned for gas, but still run closed loop via the gas ECU.

I did look at running the LPG direct off the MS - MS3 actually has support for dual fuels with different injector dead times etc, and even a 'relay switched' option for running dual injectors, but went down the easy route. I did have a link to someone else who was running MS3 with relays that switched injectors between petrol and gas so it is possible, but I can't find the site right now.. 

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7 hours ago, Landrover17H said:

Could MJ run something like this? Only I've heap of 'em laying about at the moment.

Coil Resistance: 9.1 Ohms / Low Impedance

Dead Time: 0.45ms at 14 volts
Static Flow Rate @ 43.5 PSI ( 300kPa ) w/Gas: 2200 cc/min = 210 lb/hr
Static Flow Rate @ 58 PSI ( 400kPa ) w/Gas: 2550 cc/min = 240 lb/hr

Connector: Denso / Sumitomo
Injector Length: O-Ring to O-Ring: 1.5. / 37.5 mm
Injector Body Diameter: 16mm
O-Ring: 14.5mm Viton

MJ can't run injectors, it's a cut-down MS for ignition ONLY.

MS can run fuel only, or fuel + ignition, or ignition-only, depending.

9 Ohms per injector, 4 injectors per channel, I believe that's within MS's capabilities although you MAY need PWM current limiting. MS2 would definitely have the resolution to do it.

Rover injectors (ERR722 I think) are specced:

(forum mucked the table up but you get the idea)

Part Number lbs/hr cc /min grams /min PSI BARS lbs/hr cc /min 80% 95% Feed Imped
ance
Application

n-H

0-280-155-787 16.75 176 126.6 43.5 3.0 16.75 176 25.8 30.6 EV6 High

Range Rover - Land Rover Discovery 4.0l, v8-4.6l

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Whilst it 'can' be done, looks to me, as Jon says, the 'easy' route is to piggy-back the MS with an dedicated LPG ECU. Kinda' counter-intuitive, but without a shed-load of messing, likely more straight forward and keeps everything distinct/separate. And a used LPG ECU comes dirt cheap.

Only I rarely run petrol, it's a Get-me-home fuel for when the gas tank empties, yet to get the LPG ECU to work well, I see a mess-about with petrol for quite a while. That's £3-400 in petrol or a rolling-road bill for £4-500, or both. Else, it'll be 'attempting running before I can walk'. All that adds to the bill,  the time and hassle. Then repeat for gas. Not attractive, my current set-up works extremely well. Truly 98% of my miles is via gas which is dirt cheap.

Forgive me, I'm sure it can be made better still, but I'm not sure it'll be worth the hassle.

Edited by Landrover17H
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My setup seems to be working fairly well so far - and the gas ECU takes care of all of the 'fiddly' stuff - gas temp compensation, start on petrol and auto switch over, switch back to petrol on low gas, vacuum compensation on the regulator etc..

After a few teething issues (which are all down to me not having done this before!) it will switch over to gas almost imperceptibly and seems to run as well as on petrol with virtual zero setup on the gas ECU side.

One thing - as you aren't EFI currently, the gas ECU acts as a 'modifier' to the petrol injector signals - so without the signals the ECU won't be able to control anything - most of them can't run fully standalone. You'd probably need to upgrade to a megasquirt, run 'dummy' injectors (just resistors?) and have the gas ECU run from that. I don't think it would be too much of a problem, just a bit non standard..

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Slightly off-topic. I met a man this weekend who had been warned-off LPG on a Rover V8, by a Rover specialist. He claimed that LPG burns hotter and threatens the cylinder liners.

 

I ran LPG in my 3.9 V8 for at least 80 000km and eventually one liner came loose and 2 more looked dodgy, when I stripped the engine. 

 

Is there any truth to the hypothesis? My engine was never overheated according to the temp gauge,

 

Cheers Charlie

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Not really no.

But that's just my opinion.

It's also my opinion that 'Rover specialists' are there just to make maximum wedge out of you for very little substance (I am looking at you RPI.....).

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10 hours ago, Chazza said:

Slightly off-topic. I met a man this weekend who had been warned-off LPG on a Rover V8, by a Rover specialist. He claimed that LPG burns hotter and threatens the cylinder liners.

 

I ran LPG in my 3.9 V8 for at least 80 000km and eventually one liner came loose and 2 more looked dodgy, when I stripped the engine. 

 

Is there any truth to the hypothesis? My engine was never overheated according to the temp gauge,

 

Cheers Charlie

Absolute gobbeldigook. Been running LPG for over 100k kilometres in my 4.6 Rover V8 (you know, the one people love to think has liner issues - they don't), no issue at all.

As for getting rid of the LPG ECU. Yes please. In my experience they're annoyingly fiddly things that never seem to work right. I've got an AEB something-or-other currently, and it's just carp tbh. Needs the main connector spraying with contact cleaner every so often or the RPM signal craps out. The ground bus on the ECU basically burnt itself out, had to tie all the grounds together outside the ECU to prevent that from happening (suggestion from an LPG forum).

All the fiddling with gas pressure and such just seems superfluous. The evaporator has a MAP line to correct gas flow, so does MS, and the rest you can just solve with closed-loop trimming from the lambdas.

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5 hours ago, elbekko said:

Absolute gobbeldigook. Been running LPG for over 100k kilometres in my 4.6 Rover V8 (you know, the one people love to think has liner issues - they don't), no issue at all.

As for getting rid of the LPG ECU. Yes please. In my experience they're annoyingly fiddly things that never seem to work right. I've got an AEB something-or-other currently, and it's just carp tbh. Needs the main connector spraying with contact cleaner every so often or the RPM signal craps out. The ground bus on the ECU basically burnt itself out, had to tie all the grounds together outside the ECU to prevent that from happening (suggestion from an LPG forum).

All the fiddling with gas pressure and such just seems superfluous. The evaporator has a MAP line to correct gas flow, so does MS, and the rest you can just solve with closed-loop trimming from the lambdas.

I forget how many miles my Grandy has put on his Range Rover classic with LPG. Never had any issues with it! 

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Yeah, the LPG / CNG naysayers are all the same. Our, er... 'Rover V8 expert' likely couldn't find his own a%6se with both hands. Agreed, lashed-in, any LPG/CNG system will trash the V8, or any engine come to that. But done right?

Here I quote from others on the subject:

"It's taken time to understand, yet aside from houses, I can't think of many things I've done where I've made more money for less effort. Because I did 'make' money. And assuming the naysaysers are right, how bad has it got to be before it's no worth the effort."

If you're going to run a vehicle, it makes sense to run it on the cheaper fuel. Me? Having run vehicles with LPG or CNG for near 20 years, I'm £20,000 up -  at least. To me, that's a lot of money. Have I ruined all my V8s? How many did you want to ruin? If I did, I'm left with a heap of change in the pocket?

Meanwhile, I've sat on my backside, and had my motoring subsidised by the same naysayers. Yup, the very same idiots paid for me. About 25-30 of them paid duty on petrol or diesel, such that I wouldn't have to. And it's legal. Anyone incapable of grasping that reality is no 'Rover V8 expert'.

Edited by Landrover17H
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