Injecting Liquid LPG

[mitsuko]

Yes , the Volvo setup is a first generation vialle .
The pump is the achilles heel . Won't last for 25.000 km .
The next generation pumps is a little better .
The pumps , I think , are rpm controlled by the ecu .
They are constructed like a 3-phase asynchronous cage
motor , and require substantial electronics to get them going .

I'll try to make some pictures next sturday of the components .
Or check the yahoo group foto section .
Folder called PAT , there where pictures once .

I'm dutch speaking , and I've send a lot of emails
to the vialle company in Holland . Never got a single reply .
Guess they don't like diy people .

The injectors are put on the IM by vialle itself .
Injector pockets cannot be obtained , you have to ship the manifold
to them . The injector itself spray's on the side .
At a 90° angle so to speak.

Don't know where they aim them , but I've heard of problems
with ice blockages inside the runners . Guess they have to be dead on the intake valve . Best bet imho is to get rid of the petrol injector and put the lpi injector in its place .

The engine was an I5 ( not an audi ) non turbocharged .

The lpi engine management , wich I also have from the volvo is an 68HC08 based . I can even extract the hex dump out of he eprom in case you'd like to dissasssemble it .
The management reads the petrol injector pulses , and recalculates them
for the lpi injector .
Altough vialle states they have sequential injection , I can proof
that their setup is a batch system , just like ms .
Each injector has its own driver , lm1949 based . But all the drivers
are tied together to a single . No way to do sequential with that .

I can obtain these injectors , and maybe a tank with pump from a friendly dealer I know . If I'm not mistaking , one injector is abt 150 euro .
Tank with pump close to 700 euro .


I'll make sure to post some pictures , and explain how I think some of the stuff functions .

[roundman_fabrications]

So by my calculations, we're talking almost $200 USD per injector. Pretty pricey, huh?
That eats into the fuel cost savings aspect pretty heavily, and would only leave me with the glory of having something unique.
I'm confident that I can design and build all the peripherals (with the exception of the injectors of course).
Do you know what the injector impedence is? Amp draw? It would be helpful to know if the Flyback board (upgrade) can handle them.
The whole system would be much easier to set up and control for a specific application like drag racing. Short run, good ambient temperatures, WOT, etc.
I'll look for your pics, and look forward to more.
Thanks Pat

[mitsuko]

Injectors are very very low-Z .
About the lowest i've ever seen . Half an ohm , maybe less .
That is why each injector has its own peak and hold
driver . The hold current is then pwm 'd by the lm1949
to keep operating temperature of the drivers within accepable
limits .

This circuit however isn't that hard to duplicate ,
and all the parts , ecxept for the lm1949 is standard material .
Digikey has the lm1949 , so that's no problem either .
So as the input of the drivers is a simple logic input , megasquirt can drive them directly off the main chip .
No need for flyback or fets or fet drivers .
I've already designed a special megasquirt without these parts .
Makes the pcb a lot smaller .


Pat

[roundman_fabrications]

Ain't nothin' easy, is it?
I'm having trouble locating the Yahoo user group foto page you mentioned. Haven't learned my way around well yet.

[mitsuko]

http://photos.groups.yahoo.com/group/me ... %26.view=t

Here's the link , Hope it works

[roundman_fabrications]

Anyway, may sound crazy, but here's the diesel injector type I was referring to - eBay ads NOT allowed on these forums/ebaymotors/ws/eBayI ... gory=46098
These will get cheaper as the "new" wears off.
Now to find some tech information.
I'm assuming super low Z, since the diesel system is probably operating at somewhere around 100-140 Bar.
I also wonder if they require the lubricity of the diesel fuel to operate. LPG is so dry.

[bcal]

I found this thread while searching for information on LPG injection.
Here in Oz there is a company that makes injectors that are a direct replacement for standard fuel injectors. From what I can tell they are variable flow and are set to match the original injectors charateristics so that the OEM ECU can be used.
If that's the case then they should also work with a megasquirt.
Here's a link to their site.
http://www.gas-injection.com/lpg-gas-in ... ogies.html

A typical conversion cost about $2500AUS so I wouldn't reckon that the injectors alone would be all that expensive.

[mitsuko]

Knowing the physical caracteristics of lpg , I cannot believe that
story of petrol injector emulation .
Nor the story of increased power with gaseous lpg injection .

Apart from that , there's no reason why megasquirt couldn't control these injectors .
You'll also need the vaporiser / pressure reducer unit

Pat

[roundman_fabrications]

I found the owner of BDE, Ltd. (now closed and the rights to the liquid injectors sold) today. I spoke with him on the phone this evening.
BDE provided the injectors for the vehicle in the Ketterling paper (the link is posted earlier in this thread by miked).
They are true liquid (16 BAR) injectors, except high impedance (unlike Vialle's).

[roundman_fabrications]

http://patft.uspto.gov/netacgi/nph-Pars ... d-e&d=pall
(some of Mr. Bennett's patented inventions)