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Discussion Starter · #1 ·
OK I want to know if it is worth putting T5 on two cars that we have.

My 1993 T16 Lucas
and my dads a 1990 non turbo

Iv'e read up the T5 thread at the top and a few other on the web, and I am just trying to get my head around it and if it will do what I want.

I'm interested in the 1995 ng900 as a donour as I read that it is much more simpler than the 9000 loom.

We want to run the cars as dual fuel (predominantly LPG) as LPG is still half the cost here in australia.

1. does it need to be a turbo loom?

2. Is there any advantage having T5 on my 900 turbo? or will I loose all the advantages when I go with LPG?

3. same as question 2, but on the 1990 900i?

thanks everyone
 

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I assume you are going to "fog it" or use an LP carb (mixer) ahead of the throttle plate and not try and inject the LP with LP injectors, no? I think you will loose everything when you run the LP system. You'll need to shut down the gas system as it is not good to fire the injectors dry all day. On the turbo that would mean the LP would be introduced ahead of the turbo.
I know over here, on the propane powered delivery trucks they use a modified system that allows for propane to be injected into the manifold in place of the gasoline system, but they are not duel fuel. Never done a conversion on a electroinc fuel injected engine so not sure how they do it. If the timeing portion is "stand alone" (independant of the fuel injection part of the system) then I can see it working. If it is all tied in (and I think it is) then you'll have problems.
I think the best thing is to find a fleet of trucks set up for duel fuel and talk to the mechainic that maintaines them, they will have a good idea of the problems assocated with duel fuel on a modern electronic engine.
 

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Quite a few problems will be caused by the ion-sensing in the spark plugs for the engine position sensing... I'm guessing.

For the 900i the main benefit would have been saving fuel from the sequential injector firing. But if you are using LPG then you won't be using standard injectors so the fuel-saving won't be there. On the flip side, of course you are going to save money by using the cheaper fuel so that won't matter.

I'm pretty sure you can get solenoid LPG injectors. Would have to get high-impedence injectors to avoid compatibility issues with the T5. The ECU would have to have a serious bit of mapping done to get the best out of the LPG. That's assuming the LPG does not mess too much with the ion-sensing.
 

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He said he wanted dual fuel which just about limits the LP funtion to a mixer ahead of the throttle plate. I know of no injectors that can be used for both fuels. Any way you look at it, I don't think it will be simple nor idealized for either fuel. Which is why most LP powered trucks now made are for vapor fuel only (LP/NG) and not gasoline also.
 

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Discussion Starter · #5 ·
He said he wanted dual fuel which just about limits the LP funtion to a mixer ahead of the throttle plate. I know of no injectors that can be used for both fuels. Any way you look at it, I don't think it will be simple nor idealized for either fuel. Which is why most LP powered trucks now made are for vapor fuel only (LP/NG) and not gasoline also.

true, but I am open to dedicated LPG, what I want to know would T5 work to control gas injectors? as I have been told that it is not a feasable option with the c900 cpu etc.

As of now the only option I have with the car is dual fuel, with as you said a mixer ahead of the throttle body but after the turbo, going for a lpg tank where the petrol tank is usually fitted, and fitting a 22litre petrol tank just infront of the rear axel (there is room) have tank made!!

Maybe I should be asking in the ng900 forum if they have had experience with vapor lpg injection using the T5? and replacing the injectors?
If there is a kit for the ng900 and I had T5 would there be any reason this would not work?

Obviously there would be a bit of customising.
 

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.

As of now the only option I have with the car is dual fuel, with as you said a mixer ahead of the throttle body but after the turbo, going for a lpg tank where the petrol tank is usually fitted, and fitting a 22litre petrol tank just infront of the rear axel (there is room) have tank made!!
I don't think that will work, you'll have to put the mixer at the inlet of the turbo (with vapor, no problem with the fuel dropping out of the air like gas can) as the regulators are not designed to work on the presureized intake. This would preclude useing a BOV that vents to the engine compartment
Mixer systems work on a the demand/flow of the air thru the mixer being below atmospheic pressure. If you tried to place after the turbo it would shut off the flow. There might be someway to modifie the regualator so it "senses" the manifold pressure but that would be even more complicated, and require a regulator that can take being pressureized in places where they aren't normally. I have done several LP and duel fuel conversions but only on "carb'd" engines.
All in all, I think if I wanted LP on my Saab. I would have to think long and hard before picking up a wrench or buying anything.
 

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Discussion Starter · #7 ·
I don't think that will work, you'll have to put the mixer at the inlet of the turbo (with vapor, no problem with the fuel dropping out of the air like gas can) as the regulators are not designed to work on the presureized intake. This would preclude useing a BOV that vents to the engine compartment
Mixer systems work on a the demand/flow of the air thru the mixer being below atmospheic pressure. If you tried to place after the turbo it would shut off the flow. There might be someway to modifie the regualator so it "senses" the manifold pressure but that would be even more complicated, and require a regulator that can take being pressureized in places where they aren't normally. I have done several LP and duel fuel conversions but only on "carb'd" engines.
All in all, I think if I wanted LP on my Saab. I would have to think long and hard before picking up a wrench or buying anything.

I took the car in to a lpg convertor fitter, who does LPG conversions on high powered turbo V8's he had just finished a 400hp holden,
now I migh havesaid it wrong, he said he would put a mixer infront of the throttle body, I'm certain it was vapour, as it was a new kind of setup not the old spud kind.

and yes I am thinking long and hard been looking and reaing for 2 years now :roll:
 
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