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From: Peter Hill on 16 Apr 2006 17:07 On Fri, 14 Apr 2006 08:59:09 +0100, Tom Woods <news(a)NOPSAMtomwoods.co.uk> wrote: >On Thu, 13 Apr 2006 08:39:34 +0100, Austin Shackles ><austinNOSPAM(a)ddol-las.net> wrote: > >>On or around Thu, 13 Apr 2006 00:30:25 +0100, Peter Hill >><peter.usenet1(a)nospam.demon.co.uk> enlightened us thusly: >> >>[snip good exposition on why it won't work] >> >>OK, so how do you do liquid-phase injection? Did I gather rightly that LDV >>fitted this to the Convoy, or was that simply a different kind of SGI? > >I have been told that Vialle make a LPI kit > >This thread (http://www.saabforum.nl/viewtopic.php?t=9102) is about it >(but not in english) > >From the picture it just seems to be using 4 solenoids (above the >intake manifold), with 4 flexy pipes going from them to the manifold >where the petrol injectors go in - Sounds fairly simple! > >The car in the picture has K-jet too. > >I would like to know more about the vialle system! Does it use special >injectors too? > >There must also be a special LPG ECU to control the injectors, but i >suppose that if you were determined you could use something like a >megasquirt kit to control them yourself. > >Has anybody got and prices for vialle kit? AFAIK you have to buy a whole brand new car with it fitted. I don't think any LPi is retro fit. I suspect the injectors owe more to designs for common rail HDi than petrol systems. And nothing at all to do with old mechanical K-jet or spill valve diesel systems. Had someone wander in here last year with a Ford LPi. LPG pump had failed. Pump is in tank. It seemed that the tank was welded round the pump assembly with no access to maintain pump. New tank with pump was quoted at ?1500. I think that was ICOM system. http://www.icomitalia.it/home_eng.asp http://www.cleanfuelusa.com/index.asp?navid=26 for Trucks 100% conversion so don't expect more than 30bhp/injector so only useable on sub 120bhp 4 pots like 101bhp FIAT Multipla (bifuel). http://www.italiaspeed.com/newmodels_multipla_2002.html Other firms are:- Biphase who supply system for Mexican built Ford pickup with 100% LPG V8. They must be good Dubya has one on his ranch. I think they have just changed the model and don't make the LPG version anymore. It may have been a retro fit kit 6 years ago but there were some changes in US law and I think it went pear shaped except for OEM. http://www.eere.energy.gov/cleancities/conference/2003/pdfs/petrich_biphase.pdf Used in tank pump to run fuel rail at higher than tank pressure. Let returning fuel vaporise to cool fuel supply. Cummings Westport who make school bus and truck engines. Again a 100% LPG conversion as they use spark ignition and lower compression on a modified diesel block. http://www.cummins.com/na/pages/en/products/bus/ratingsalternativefuel.cfm Quite pathetic output for size of engine 195bhp from 5.9L = 33bhp/L. Unbelievably, given the low output, it's even turbocharged. http://www.cummins.com/na/pdf/en/products/4103568.pdf Runs off tank pressure except for very low temps (Arctic). This also shows a graph of pressure rise with temperature in liquid propane system. http://www.sleegers.on.ca/pt_liquid_propane.shtml As you can see from the propane pressure graph the tank vents excess pressure at 315psi (21bar) which would be at 140?F(60?C) - ie during a fire. All tanks have this fusible plug to ensure a controlled and safe release of pressure before the tank bursts. It must be the first item to fail on the system, everything else in the system has to take a higher tested pressure (500psi?) before bursting or otherwise failing. Brainiac- science abuse, managed to by-pass the operation of a fusible plug by using thermite. It lanced though the tank before the temp or pressure at the plug was high enough so all the contents went up in one go. A 19Kg (38L) cylinder was quite impressive. -- 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! |