dual map ignition

[DoubleChevron]

Hi Guys,

has anyone tried one of these ?

Rover V8 LPG KIT MAF Timing Advance Propane MSD Autronics 40672 CNG Ignition | eBay (http://www.ebay.com.au/itm/201528122919?euid=379824f0a43b45dfbe40d7ccc8bfa329&cp=1)

seems quite cheap for the effort and design work that would have gone into it. It appears they are selling off old stock as there isn't any real market left for them.

My old '92 Range rover runs great on lpg ('cos I have the ignition way advanced), but so poorly on petrol, if I ran out of gas, I'd need to stop on the side of the road and retard the ignition to make it drivable.

seeya,
Shane L.

[Pedro_The_Swift]

That module doesn't suit any of the 4 '92 RR options,
it would take a while to check all the RR years;)

[DoubleChevron]

That module doesn't suit any of the 4 '92 RR options,
it would take a while to check all the RR years;)

Are you reading the ebay advert? There is no details there is there ? They all have electronic ignition, and I think that's the module for the hotwire MAF sensor models :confused:

I tried googling for details, but the manufacturer has removed them from its website.

seeya,
Shane L.

[DoubleChevron]

They have put up the wiring diagram.

This WOULD work right? Anything later than the flapper Rangies (ie: discos etc) use MAF sensor right?

https://www.aulro.com/afvb/images/imported/2016/04/313.jpg

Buggered if I can understand how a MAF sensor influances timing though. It should influance mixture not timing :confused:

seeya,
shane L.

[Roverlord off road spares]

The Maf does not control the distributor, which is what controls timing, bt vacuum and by centrifugal advance.
I found this on a UK site, this gizmo replaces the ignition AMP on the distributers so that spark advance is changed.


https://www.aulro.com/afvb/images/imported/2016/04/266.jpg New New !!!! What is the "Advance by retard system")?.

LPG can indeed be as economical and powerful as fuel but the issue is with the ignition timing and spark intensity due to the slower flame front of LPG, Either upgrade to a Mallory duel point. as above( Carb type only) Or fit our unique new retard by advance system (Electronic ignition types only) We have just released this devise that replaces the original ignition amp on (or separate from) your distributor, (we can supply it with a brand new distributor also) and allows you to set base timing to 18 deg. thus giving a healthy 38 - 40 deg of advance when on lpg this will be the answer to all LPG prayers, and what's better when running on petrol it retards the ignition back to std 8 idle - 28 deg. @4000.
https://www.aulro.com/afvb/images/imported/2016/04/267.jpg https://www.aulro.com/afvb/images/imported/2016/04/268.jpg

[DoubleChevron]

The Maf does not control the distributor, which is what controls timing, bt vacuum and by centrifugal advance.
I found this on a UK site, this gizmo replaces the ignition AMP on the distributers so that spark advance is changed.


https://www.aulro.com/afvb/images/imported/2016/04/266.jpg New New !!!! What is the "Advance by retard system")?.

LPG can indeed be as economical and powerful as fuel but the issue is with the ignition timing and spark intensity due to the slower flame front of LPG, Either upgrade to a Mallory duel point. as above( Carb type only) Or fit our unique new retard by advance system (Electronic ignition types only) We have just released this devise that replaces the original ignition amp on (or separate from) your distributor, (we can supply it with a brand new distributor also) and allows you to set base timing to 18 deg. thus giving a healthy 38 - 40 deg of advance when on lpg this will be the answer to all LPG prayers, and what's better when running on petrol it retards the ignition back to std 8 idle - 28 deg. @4000.
https://www.aulro.com/afvb/images/imported/2016/04/267.jpg https://www.aulro.com/afvb/images/imported/2016/04/268.jpg

Yes, I figured the later integrated injection/ignitions systems must run timing maps based on the MAF sensor input as well.

The above one would be interesting....

A&R Amp Advance Retard Igntion Power Pre Amplifer Rover V8 3.5 3.9 4.0 4.6 RPi | eBay (http://www.ebay.co.uk/itm/A-R-Amp-Advance-Retard-Igntion-Power-Pre-Amplifer-Rover-V8-3-5-3-9-4-0-4-6-RPi-/191841714382?hash=item2caaa840ce)

$300 it is though... I'd be tempted to convert to megajolt for that sort of $$$ :) I rekcon for similar money I'd have a crack at one of these:

Megajolt/E | Autosport Labs (http://www.autosportlabs.com/product/megajolte/)

By the time you buy coil packs and trigger wheel you would be at similar $$$. You could always revert back to standard in a pinch (even on the side of the road) too.

for now I'll leave it set to gas running. It certainly is a PITA though as it barely runs on petrol as I have the ignition so far advanced.

seeya,
Shane L.

[DoubleChevron]

This seems to be the cheapest/easier way to get the best lpg/petrol timing compromise. AEB 549 ... Joker:

AEB 549N Joker-N Timing Advance Processor | Tinley Tech (http://tinleytech.co.uk/shop/lpg-parts/aeb-549n-joker-n-timing-advance-processor/)

I wonder if anyone sells them in Australia. They would be about $150.00aud delivered to your door from the UK.

seeya,
Shane L.

[DoubleChevron]

Well I fitted up one of those AEB 549n units. Very simple, I just flicked it over to 8cylinder, 9 degrees advance, no advance on idle or over-run. I reset the timing to 8 degrees and fired her up ............. It sounded absolutely spectacular. I took it for a spin up the court and it revs out much more cleaning, smoothly and quickly than having the timing set to ~12degree.

OK, that test is good, now what I wanted was it drivable on petrol ... 'cos it's downright bloody dangerous if you run out of gas........ Flicked it over to petrol and she died in the arse. Would rev ok in nuetral, but wouldn't run under load, certainly with the clutch out you can't rev it past 2000rpm ....................... Hmmm...

So I took it home and bypassed the AEB unit and had the same behaviour .... Well bugger it all, I sure did mis-read the symptoms, I thought it was breaking down and dying as the igntion was far to over-advanced to run on petrol. I whipped the lid off the dizzie and check the weights and 'vac advance...... But she runs so incredibly sweetly on gas it simply can't be ignition.

I struck something similar to this on an old Citroen CX before with a flapper type air flow system...... Which on that car I verified by unplugging the air flow meter and seeing if it would run .. which it did but poorly (as they must use a default map).

Soooooooooooo, I unplugged the mass airflow meter, and the rangie will now run on petrol, kinda poorly but it will rev out and run on petrol. I swapped it with the mass air meter off the other car and had the same symptoms.

Does this sound familiar to anyone ?? Is it a sensor unplugged somewhere ? The fact it runs ok with the air meter unplugged says the injectors and fuel system is flowing adequate fuel. Maybe I have a wire chaffed through somewhere. So if no-one has any suggestions I'm about to waste many hours following wiring back into the cabin and checking all the connections and plugs :(

But hey, it's bloody lovely running on LPG :angel:

seeya,
Shane L.

[DoubleChevron]

I just thought I'd add an update here. The car is absolutely transformed in the way it drives with that ignition processor. Idle is smooth and has a real v8 beat to it now. It hammers .... The difference to the cars running is amazing. I'm probably using only 2mm of throttle in all gears to keep up with the traffic, only it revs out much harder and smoother than it ever has before.

I didn't expect an improvement when running on gas, I thought I'd get an improvement in the petrol running.... I'm extremely happy with the AEB unit. $150 very well spent!

seeya,
Shane L.

[Bradtot]

Hi Shayne
Based your glowing report I have just ordered the dual advance joker from tinley tech.
Can't wait to see what improvements in power and smoothness I get.
I have been tossing up over many years to get one of these and now it's done.
Brad:):)

[DoubleChevron]

Hi Shayne
Based your glowing report I have just ordered the dual advance joker from tinley tech.
Can't wait to see what improvements in power and smoothness I get.
I have been tossing up over many years to get one of these and now it's done.
Brad:):)

Yes, it is remarkable. I made sure I changed nothing else before fitting it so I could verify it was the only change made. I've noticed there is now a flat spot below 1200rpm. This will be because I have "no advance at idle" switched on. So it obviously flags anything below 1200rpm as idling. Obviously this is no biggie :) I could always just flip the dip switch so it always has advance.

After I've thrown some new plugs and leads into it, I'll try adding in more advance and see how it likes it (it will probably depend a lot on the quality of LPG how much advance can be ran).

seeya,
Shane L.

[Bradtot]

Hey Shayne
I have my joker fitted...what settings you running?
Yes it's smoother running and very light on the throttle....I have my advance "on" at idle and 15 degrees advanced ..this seems the best for me .but am curious on what setting you have..
I haven't retarted the ignition timing as its runs well on petrol..in fact switching on the go between petrol and gas, petrol is still more powerful...especially noticeable up hills..
The engine had done 50 k since a complete 3.5 to 3.9 rebuild..
Dizzy weights and rotor and cap all good..
Brad:)

[DoubleChevron]

Mine was flat as a tack above 3200rpm on LPG before fitting the processor. I think LPG require a lot more advance at low revs, but less than petrol at high revs. So if you still have your static timing considerably advanced, you may find it flat at higher revs. Try resetting the static advance back to ~ 8degrees.

You see if you already have lots of advance in there, and the processor goes and adds more in, you may kill the top end. I'm assuming AEB know what they are doing and have added the advance as a curve. ie: it'll not add the full advance settings at higher revs. Mines still set to 9degrees from memory. I'm so happy with the way in goes on LPG I haven't got around to messing with it ( Getting it running on petrol, even remotely as well as it does on gas is a higher priority).

Mine hammers on LPG. I had a fellow AULRO member call around on sunday a lend me a MAF sensor to try. So mine now runs ok on petrol below 3000rpm ... but dies in the arse still at higher revs on petrol (at least it runs fine now for normal driving on petrol). I'm thinking I have either a blocked fuel filter or weak pump. So there isn't enough fueling for wide open throttle or high revs on petrol.

seeya
Shane L.