Remapped ECU vs. LPG System
in [LPG]
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From: Dav-G on 3 Mar 2007 17:03 Dear all, I've had my original ECU remapped on my '02 Volvo V40 1.8i to improve performance. Now I've got an LPG system fitted (Zavoli Alisei-N multipoint sequential), how do I ensure that the LPG system is also taking advantage of my remapped settings in the original ECU? Someone mentioned 'recalibrating the LPG system to the ECU' to do this. What do they mean? How is this done? Are there any other ways of ensuring the LPG system is using the remapped values from the original ECU? Thanks, Dave.
From: Tim.. on 3 Mar 2007 17:25 "Dav-G" <daf(a)tonfab.com> wrote in message news:KM6dndr0PI5MbXTYnZ2dnUVZ8sitnZ2d(a)mailbox.co.uk... > Dear all, > > I've had my original ECU remapped on my '02 Volvo V40 1.8i to improve > performance. > > Now I've got an LPG system fitted (Zavoli Alisei-N multipoint sequential), > how do I ensure that the LPG system is also taking advantage of my > remapped > settings in the original ECU? > > Someone mentioned 'recalibrating the LPG system to the ECU' to do this. > What do they mean? > How is this done? > Are there any other ways of ensuring the LPG system is using the remapped > values from the original ECU? The LPG ecu measures petrol injector ontime via the wiring harness and subsitutes a corrected LPG injector on time accordingly, so it should automatically fuel at an optimum level. The re-mapped petrol ECU will possibly have more aggressive ignition advance than standard too, which is a good thing for LPG.. Why not get it on the rollers and see how it compares petrol / lpg.??? tim. ..
From: Dav-G on 3 Mar 2007 20:28 Hi Tim. So you mean that, regardless of whatever fuel pulse on-time and duration the petrol ECU has, the LPG ECU will always refer to its own, ignoring any such remapped data..? So, my petrol ECU remapping won't be passed on to my LPG ECU? So, to get an equally Sporty feel from my LPG system, I'd have to have IT remapped as well..? I thought the LPG system merely mirrored the petrol system, injecting when the petrol system did, for the same length of time as the petrol system did..? Regards, Dave. "Tim.." <the.farm.no(a)spam.btinternet.com> wrote in message news:0oWdneABPKwraHTYRVnytQA(a)bt.com... > > "Dav-G" <daf(a)tonfab.com> wrote in message > news:KM6dndr0PI5MbXTYnZ2dnUVZ8sitnZ2d(a)mailbox.co.uk... > > Dear all, > > > > I've had my original ECU remapped on my '02 Volvo V40 1.8i to improve > > performance. > > > > Now I've got an LPG system fitted (Zavoli Alisei-N multipoint sequential), > > how do I ensure that the LPG system is also taking advantage of my > > remapped > > settings in the original ECU? > > > > Someone mentioned 'recalibrating the LPG system to the ECU' to do this. > > What do they mean? > > How is this done? > > Are there any other ways of ensuring the LPG system is using the remapped > > values from the original ECU? > > The LPG ecu measures petrol injector ontime via the wiring harness and > subsitutes a corrected LPG injector on time accordingly, so it should > automatically fuel at an optimum level. > > The re-mapped petrol ECU will possibly have more aggressive ignition advance > than standard too, which is a good thing for LPG.. > > Why not get it on the rollers and see how it compares petrol / lpg.??? > > tim. > . > >
From: Peter Hill on 4 Mar 2007 03:43 On Sun, 4 Mar 2007 01:28:00 -0000, "Dav-G" <daf(a)tonfab.com> wrote: > Hi Tim. > >So you mean that, regardless of whatever fuel pulse on-time and duration the >petrol ECU has, the LPG ECU will always refer to its own, ignoring any such >remapped data..? No. He means that the LPG injection pulse time tracks the petrol injector pulse time. LPG ECUs are stupid, they don't have "maps" they just convert pulse time taken from petrol ECU to one for LPG injector. You may on the better ones get different conversions for cold, idle, cruise and high load. If the person doing the mapping could be arsed to set it up. >So, my petrol ECU remapping won't be passed on to my LPG ECU? The LPG ECU has no mapping it's just a pulse time converter. Whatever injection pulse the petrol ECU outputs the LPG ECU converts. >So, to get an equally Sporty feel from my LPG system, I'd have to have IT >remapped as well..? No. Not unless it wasn't calibrated to your petrol injectors in the first place. If the LPG injectors need a longer on time than petrol injectors you may have a problem at high load as they can max out. For example if conversion petrol>LPG on time is 1.1 and your re-mapped petrol injectors hit 92% duty (time on/(on+off) ) then your LPG injectors need 101.2% duty, which is not possible. >I thought the LPG system merely mirrored the petrol system, injecting when >the petrol system did, Correct >for the same length of time as the petrol system >did..? Changes pulse length - injector "on" time. (what Tim said) -- Peter Hill Spamtrap reply domain as per NNTP-Posting-Host in header Can of worms - what every fisherman wants. Can of worms - what every PC owner gets!
From: Dav-G on 4 Mar 2007 20:26
Hi Peter, Can you describe what you mean by 'duty time'? E.g. 92% of what? 'Time on/(time on + time off)': What? Surely the limiting factor would be the duration the inlet valve is open for. Do you mean 100% = inlet valve open total time? All sounds very interesting. So, the LPG system tracks the petrol injector on-time and pulse width (thus also being affected by remapping), but modifies it into an LPG-friendly version, with slightly different (earlier?) on-time and pulse width (longer?)..? If my LPG system was fitted after my remapping, would this mean that the LPG system has been calibrated to the remapped petrol ECU? What exactly does 'calibrating the LPG system to the petrol ECU' consist of? Thank you for your insights. I'm appreciating the information! Regards, Dave. "Peter Hill" <peter.usenet1(a)nospam.demon.co.uk> wrote in message news:8n0lu2587s80fuqenomeb9gke7vqu9t350(a)4ax.com... > On Sun, 4 Mar 2007 01:28:00 -0000, "Dav-G" <daf(a)tonfab.com> wrote: > > > Hi Tim. > > > >So you mean that, regardless of whatever fuel pulse on-time and duration the > >petrol ECU has, the LPG ECU will always refer to its own, ignoring any such > >remapped data..? > > No. He means that the LPG injection pulse time tracks the petrol > injector pulse time. LPG ECUs are stupid, they don't have "maps" they > just convert pulse time taken from petrol ECU to one for LPG injector. > You may on the better ones get different conversions for cold, idle, > cruise and high load. If the person doing the mapping could be arsed > to set it up. > > >So, my petrol ECU remapping won't be passed on to my LPG ECU? > > The LPG ECU has no mapping it's just a pulse time converter. Whatever > injection pulse the petrol ECU outputs the LPG ECU converts. > > >So, to get an equally Sporty feel from my LPG system, I'd have to have IT > >remapped as well..? > > No. Not unless it wasn't calibrated to your petrol injectors in the > first place. > If the LPG injectors need a longer on time than petrol injectors you > may have a problem at high load as they can max out. For example if > conversion petrol>LPG on time is 1.1 and your re-mapped petrol > injectors hit 92% duty (time on/(on+off) ) then your LPG injectors > need 101.2% duty, which is not possible. > > >I thought the LPG system merely mirrored the petrol system, injecting when > >the petrol system did, > Correct > >for the same length of time as the petrol system > >did..? > Changes pulse length - injector "on" time. (what Tim said) > -- > Peter Hill > Spamtrap reply domain as per NNTP-Posting-Host in header > Can of worms - what every fisherman wants. > Can of worms - what every PC owner gets! |