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Hi guys im in the middle of the planning stages of my next project and im in a heated argument with myself on a fueling system. I know a lot of people are going to laugh at me and call me a tool or what ever, but im putting a RB25DET into a SWB GQ Patrol. I have had plenty of street cars but you cant have any real fun on the streets and there not the best cars off road either. So my plan came about when i thought performance you can take anywhere( and when i said anywhere i ment Anywhere-city, bush, beach, etc) any way back on the topic of fuels. Now i can go with the standard setup- fuel tank, fuel pump, pressure reg, injectors, ecu, etc. -OR- i can go for the first(at least i think it would be the first) Sequntial Multi-point LPG Injection setup ever done on a RB25DET. i can also have both.

With Fuel Prices the way they are going and the fact that it costs about 180cents($1.80) on average for a litre of 98 octaine fuel. and the fact that LPG is only 60cents ($0.60) on average for a litre of liquid petrolium/propane gas (LPG) and the fact that if you install LPG you get a Rebate of $2000 from the government. The LPG or even a Dual Fuel System Seems to be a good investment.

There is also the fact that a LPG engine is cleaner,not just for the enviroment but for the engine itself. Also it creates less wear to the bores from what ive seen as LPG doesnt wash oil from the inside of the bore like petrolium does and it also doesnt contaminate the oil like petrol does. It funnily enough has a much higher octain rating than 98 octain fuel. Previously convetional gas systems made the engine run hotter because the liquid was already vapourised before it went through the throttle body, into the manifold and into the cylinder, but with liquid gas injection the liquid is fed directly into port before the valve and then drawn into the cylinder witch as most people know liquid gases have a great cooling efect and greater cooling effect than petol witch keep engine temps down. there is also the fact that gas vaporises and mixes with air alot beter than fuel due to fuel is always majority a liquid until ignition where as with lpg the gas would mix much beter resulting in a more stable and even burn. witch by a performance fuel side of things makes LPG seem to be the way to go for a performance aplication. Due to the higher octain rating this would allow for more boost and ignition timing. Therefore creating more power. I must say ive never looked at Sausage Gas as a performance fuel before, but the more i look the more reasons to concider it.

But any way enough of me rambling on... What do the rest of you think? I look forward to seeing some peoples input/ideas and if anyone wants to help with the design or pass on any ideas for the project let me know.

Kind Regards

Mr Flwlss

Edited by MR FLWLSS

here is a site with some examples of the multi point systems i was talking about:

http://www.autogasitalia.it/db/kit2.asp?lan=eng&id=13

i have also included some pictures

post-40206-1214406472_thumb.jpg

post-40206-1214406519_thumb.jpg

Does it have a petrol or diesel in there now?

How much does it weigh? (not off the rego sticker, they usually are wrong)

I think you'd be better going down the route of RB30ET if anything, and put that on gas.

Overall i dont think its a good move, the 2k you'll get back wont even tip the iceberg on a proper system

As for the rest, thread from a few days ago

http://www.skylinesaustralia.com/forums/Lp...tr-t225078.html

the most common is the 4.9:1 ratio(i think its that) in the 4.2l and 3.0l patrols. which provides plenty of torque at the wheels. there was a long wheel base one in a zoom mag a while ago and it had a RB26DETT in it and it drifted down the street with ease and smoked 3rd. the Gq patrols all shared the same transfer case and diffs and the only difference was one had a 4.2 carby or injected motor and the other had the RB30carby job and there were 2 different gearboxes to suit the different engines. all you do is unbolt the 4.2l gear box from the transfer and swap for the rb30 one. everything else is bolt in. and the rb30 boxes are built like a brick shithouse. that guy in zoom only broke his gear box after he got close to 400rwkw or somthing like that, they are mechanicaly the same as a R33 box inside except for the output shaft and rear bearing setup for the out put shaft and rear housing. they have the same model number as well except one is the 2wd model and the other is the 4x4 model.

Edited by MR FLWLSS

hmm, think youd get pretty bad fuel economy because of the small 2.5L tryin to move a heavy car... and it is heavy.

the rb30det gearboxes are a bit more similar to the R33gearboxes, but the NA 30box is shit, wont hold anything.

you cant compare to a car in a magazine either cause who knows what "extra's" its got that it didnt mention.

but il give you a plus for thinking outside the box, however if you were to try and put a RB25det into say....a susuki vitara or something... ooo yeh that would be sweet.

Edited by -_-StRyDeR-_-

im going for a short wheel base 2 door patrol due to the weight factor. the 2 doors are pretymuch kg for kq with an r33 as far as total mass goes however the patrol has a greater rotational drive line weight so the load would be greater. but at 60cents a litre of lpg and concidering with multipoint gas injection you get pretty close to 1L of LPG to 1L of petrol if set up right the cost saving is huge. I went to ELKO auto gas supplies and spoke to the guys down there and they gave me a demmo of the multi point injection system and they are pretty awsome

these are all options. but i have to sell my skyline first. its for sale if anyones interested.just had a huge huge price drop. anyway back on topic it would be nice but i want a turbo duel fuel motor and setting up the rb30/25 setup is alot of work just for a good daily that i ca tow the go kart trailer with and take on holidays. with the smaller capacity rb25 turbo motor on lpg economy should be pretty good with respectable power.

Edited by MR FLWLSS

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