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Gas Conversions?

Stinky Rooster
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Stinky Rooster Grand Master

Stinky Rooster

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Posted

OK, I'm gonna brave the near certain flames I am gonna get for this one, but has anyone out there ever made any enquiries about a dedicated gas conversion to a series 1 RB25DET? I have been asking a few fitters here in WA (wait awhile) and all I am getting is horror stories about melted pistons and such. Now, acording to my research, LPG has a much higher RON than even Premium Unleaded so, in theory, this would be a Good Thing in regards to the tuning scope allowed, not to mention the savings in fuel costs.

The fact that the WA gubberment is now offering $2000 on top of the Federal gubberments $1000 rebate plan means that I will be spending bugger all of my own money to get this done.

My main questions about the conversion are centred around the fact that this would have to be a "blow through" set up and what effects is this likely to have on the standard throttle body? I am seriously considering this because I believe that with a gas dedicated cam grind, a purpose built exhaust and some quality time on the dyno, 200awkw would not be out of the question.

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TurboX Mentor

TurboX

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Posted

I think the "Gas Research" gas throttle body in place of std TB would compensate for turbo pressure similar to a rising rate Fuel Press. Reg. does.

Gas Injection like the new Fords have is probably the way to go though, but I dont know if this is available aftermarket or not and wether it would be able to be tuned by aftermarket ECU.

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munchstagea Mentor

munchstagea

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Posted
Here’s a quick run down on why LPG is a bad idea;

1. You need 1.3 litres of LPG to go as far as 1 litre of 98 ron.

2. The LPG tank (being a pressure vessel) has thicker walls, hence for the same outside dimensions it will hold 20% less.

3. Add 1 & 2 together and it means 50% less distance between refills compared to he same dimensioned petrol tank.

4. LPG is now 99 ron, the 110 ron dropped to get the price down

5. There isn’t an LPG system designed for RB’s, so you would need one to be made up “special”. Think lots of $’s.

6. They will use a single point gas mixer (not 6 injectors, not sequential), it will simply be connected to the throttle, more throttle opening = more gas squirted in. No fuel mapping as such.

7. Your standard ECU will run the ignition etc

8. Driveability, cold start and run, hot run etc will all suffer as a result of the poor (in comparison) fuel metering.

9. If you live in a cold area you won’t be able to drive your car until it warms up. If you don’t warm it up, drive off and accidentally use too much throttle you may well get a gas explosion in the inlet system. Not large enough to hurt you but large enough to require a top end rebuild.

And a few others I have forgotten.

:wave: cheers :P

I don't think it is a great idea...

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