ah i wondered where that thread went. Regardless, I'm not looking for price comparisions or brand comparisons, i'm looking for specific benefits of gas injection over the older style setups. I have heard that there is minimal to no power loss on a gas injected system if tuned correctly. Is this true? Will my fuel economy benefit using this setup over the older setup? If initial cost of an injection setup is not factored in, which is the more economical of the two and by how much?
What you ask is covered in that other thread, however, at present there does not appear to be any independent test results highlighting the basic performance and economy advantages of the svi system.
At the risk of repeating myself, the basic laws/facts of chemistry and physics tell us that lpg has only 75% of the energy of petrol for the same volume. Already mixer systems achieve 70-73% of the the petrol "mileage"... using official aus government fuel consumption standards for the commodore on both city and highway cycles. Based on that theoretically there would only be a 2-5% possible reduction in fuel consumption going to svi, any further reductions would simply break the common laws of conservation of energy as we know them, so Im in complete disbelief to anyone who claims a svi system is going to be 20-30% more efficient than a well setup mixer system. Ive yet to hear anything logical in response to this from anyone yet! This small difference is most likely due to the fact that we are converting engines that were designed from the ground up to burn petrol. I have read claims from some have that their lpg consumption is similar to petrol using svi, the only thing that would make sense here is if it were running to rich/poorly on petrol or that a lot of cold start/short trip usage is done.....lpg consumption rivals petrol consumption at low operating temp.
If there was no setup/initial cost difference Id go with the svi, though the present systems of having to be dual fuel and having to run petrol up to 40C could be uneconomic and unconvenient.
