New member, first post and I don't own a Magna. I do share an engine type with the 3rd Gen Magna though and that's why I'm here. Vehicle is a 96 Delica Spacegear fitted with the 3.0 24V single cam V6 which has been converted to dual fuel. I've read and heard that the ignition advance timing on lpg should be different to that for petrol and that's what I'm enquiring about now.

The Delica engine runs three coil packs in place of a distributor (and has a deeper sump), but in all other respects is the same donk as the 3G Magna. To accomodate a different advance curve I've built and fitted a Jaycar high energy ignition kit that is set up with 2 seperate timing maps that are automatically selected by a relay connected to the lpg solenoid valve and the whole lot is up and running just fine. The kit is installed purely as an interceptor on the crank angle sensor so all the original load and temperature timing changes from the original ecu will be retained. The petrol map has been left at 0 timing change for now, so switching back to petrol will be the same as always.

The correct timing advance/retard values for running on lpg are proving more elusive to find than I imagined. Most recommendations are for more advance down low and less advance up high, but the amounts of timing change vary as does the definition of down low and up high. In my searching I've read that some 3G Magnas came from the factory with a dual fuel setup and it's from these vehicles that I hope to gain some baseline info.

Has anyone with a 3G factory dual fuel setup ever worked out what the base timing advance curve looks like for both fuel types on their car ? That knowledge would give me a good place to start with punching some numbers into my lpg timing map table. Down the track I might even start to fiddle with the petrol timing curve to see if there's any free gains to be had, but for now I'd just like to get the lpg side sorted. Any help is appreciated.

New member, first post and I don't own a Magna. I do share an engine type with the 3rd Gen Magna though and that's why I'm here. Vehicle is a 96 Delica Spacegear fitted with the 3.0 24V single cam V6 which has been converted to dual fuel. I've read and heard that the ignition advance timing on lpg should be different to that for petrol and that's what I'm enquiring about now.

The Delica engine runs three coil packs in place of a distributor (and has a deeper sump), but in all other respects is the same donk as the 3G Magna. To accomodate a different advance curve I've built and fitted a Jaycar high energy ignition kit that is set up with 2 seperate timing maps that are automatically selected by a relay connected to the lpg solenoid valve and the whole lot is up and running just fine. The kit is installed purely as an interceptor on the crank angle sensor so all the original load and temperature timing changes from the original ecu will be retained. The petrol map has been left at 0 timing change for now, so switching back to petrol will be the same as always.

The correct timing advance/retard values for running on lpg are proving more elusive to find than I imagined. Most recommendations are for more advance down low and less advance up high, but the amounts of timing change vary as does the definition of down low and up high. In my searching I've read that some 3G Magnas came from the factory with a dual fuel setup and it's from these vehicles that I hope to gain some baseline info.

Has anyone with a 3G factory dual fuel setup ever worked out what the base timing advance curve looks like for both fuel types on their car ? That knowledge would give me a good place to start with punching some numbers into my lpg timing map table. Down the track I might even start to fiddle with the petrol timing curve to see if there's any free gains to be had, but for now I'd just like to get the lpg side sorted. Any help is appreciated.

From my dealings with my sole LPG powered 308 Holden V8 engine that i did lots of research on,LPG requires lots of static or initial timing,but less total advance than the equivalent petrol engine,for example,with petrol,i was running about 6 degrees static and a total advance of about 36egrees (mech and vacuum advance),on lpg,im runnin a recurved dizzy that allows nera on 20 degrees initial and about 10 mechanical (vac advance deleted)

may be slightly different on a late model engine,but the burn charateristics of LPG remain the same

Steve

these newer engines dont use vaccum advance, being efi, so its all int he programming, in which case, you are on the right track in regards to finding the right spot for it. To complicate matters what people are telling you may be based on different compression ratios. The last lpg car i was around used petrol like ignition timing values but on a cpmpression of nearly 13:1

Did you find any advantages in adding any static timming on the lpg side of things?
I have pajero i wouldnt mind doing the same (3coil setup as well). They are quite laggy just of idle would like to improve of the mark response if possible by advancing. Its a little better with a bored throttle body but i believe the static timming lets it downb as far as i can tell and from what i have been told.
Another fellow i know installed a unichip to overcome this. From what i remember he added another 6-8degrees which made a remarkable improvement down low not sure about the top end.
Do you have a part no.?
Does it come in kit form or is it already assembled?
Regards

I've got a factory dedicated gas 3.5 engine that uses a Mitsubishi MR988726 ECU (4 spd AT Without TCL) with an IMPCO navigator (MR932268) that plugs into the loom and tricks the ECU into thinking it's still firing the injectors. The ECU still looks after the ignition timing/auto transmission etc as if it was a petrol engine.

Cheers

Thanks for the responses. The 308 findings agree almost completely with everything else I've read about lpg on the net, there was only one bloke with a Land Rover in the UK who had a dyno report showing even more advance at higher revs produced better power, where most advocate less advance. The points about newer engines, without vac advance and with different comp are relevant as a lot of what I've read relates to older 2 valve V8's which might influence what they found with timing alterations. The module I've fitted comes as a kit from Jaycar so you need access to someone who can assemble it before it can be fitted. The kit p/n is KC5442, the Hand Controller/Programmer is KC5386 and I also did the knock sensor add-on KC5444 before finding that I don't have a knock sensor, which is the same for the 3G Magna from what I've read on here ? The module has only been in a week so too early to make any solid calls yet other than it seems to pick up quicker and need less throttle around town, but that's subjective. For initial lpg timing changes I've guestimated 10 deg adv from idle to 2000, 0 deg at 3000 and 10 deg retard at 4000. The factory dedicated gas 3.5 setup might be helpful, do you know what the base timing curve looks like for it ? Is that ecu part number the one that the factory fitted just for the lpg fuelled models ? The Impco injector emulator I understand as I had to get a similar one from Apexus to stop my CEL from coming on.

I'd still be keen to hear from anyone with the factory 3.0 dual fuel setup or from anyone that knows what the base lpg and petrol timing curves are for it as I figure the factory probably put a bit of engineering time into developing it and naturally I'd like the benefit of that specific knowledge as a reference point for my changes.

Hi Delicia, PM Type40 he may have some related info.

Not sure what the base timing curve looked like. ECU's with the same part number are also used on petrol models. The distributor used also has the same part number as on a petrol engine. From memory the base ignition timing was the same as a petrol engine. You could try asking IMPCO for some tech info on the navigator internals ie: does it alter the timing etc.

Cheesr

Update after a week of fiddling. Bought an in-car accelerometer to try and monitor what the nett effect of the timing changes was doing to acceleration. Found this engine likes lots more initial advance below 2500, tried 2 degree increments from 0 to 22 degrees and found +18 is the sweet spot. Remember this is extra advance on top of whatever the original petrol timing is. Nothing much happens from 0 to 10 degrees extra advance then it gets gradually better to 18 and then tapers off again past that. Responsiveness off the line is better and the 0-60 foot times on gas are now better than petrol on every run and this is with a conventional mixer style lpg setup and an auto trans. Not sure what if any longer term damage this might do and haven't used enough fuel to see if fuel economy has changed yet, but below 2500 rpm it certainly feels crisper and needs less throttle to maintain a steady speed than it used to.

I suspect the factory LPG timing is the same as the petrol car. I interrupted the feed back from the barometric pressure sensor which - according to the manual - gives 5 degrees advance to base timing (on a Magna). I only use this when running on LPG, but even 5 degrees has made a noticeable improvement down low, easier cruising, quicker response. It's not the perfect timing mod but I would recommend people on LPG to give it a try.

how is the jaycar ignition controller going?




Thanks for the responses. The 308 findings agree almost completely with everything else I've read about lpg on the net, there was only one bloke with a Land Rover in the UK who had a dyno report showing even more advance at higher revs produced better power, where most advocate less advance. The points about newer engines, without vac advance and with different comp are relevant as a lot of what I've read relates to older 2 valve V8's which might influence what they found with timing alterations. The module I've fitted comes as a kit from Jaycar so you need access to someone who can assemble it before it can be fitted. The kit p/n is KC5442, the Hand Controller/Programmer is KC5386 and I also did the knock sensor add-on KC5444 before finding that I don't have a knock sensor, which is the same for the 3G Magna from what I've read on here ? The module has only been in a week so too early to make any solid calls yet other than it seems to pick up quicker and need less throttle around town, but that's subjective. For initial lpg timing changes I've guestimated 10 deg adv from idle to 2000, 0 deg at 3000 and 10 deg retard at 4000. The factory dedicated gas 3.5 setup might be helpful, do you know what the base timing curve looks like for it ? Is that ecu part number the one that the factory fitted just for the lpg fuelled models ? The Impco injector emulator I understand as I had to get a similar one from Apexus to stop my CEL from coming on.

I'd still be keen to hear from anyone with the factory 3.0 dual fuel setup or from anyone that knows what the base lpg and petrol timing curves are for it as I figure the factory probably put a bit of engineering time into developing it and naturally I'd like the benefit of that specific knowledge as a reference point for my changes.

The Jaycar ignition controller has only been in place for a few weeks and is working fine. I made final minor adjustments to the curve a couple of weeks back and am now just driving it to monitor fuel economy and drivability. It definately feels better down low now, but beyond 3000 rpm I can't feel any performance difference at all. Economy doesn't seem to have changed either way but I'll do a few more tanks before making a conclusion.