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I supported Toymods
Location:
Toodyay, WA
Registered:
July 2002
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1G-GTE Economy
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Tue, 23 July 2002 11:00
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Hi guys,
Looking to spruce up a RA28, with a new donk.
It seems that the 1G-GTE is the best motor for this job, as the 18R-GEU seems a little hard to come by these days...
But, how much fuel do these things use???
thanks,
CamZH
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I supported Toymods
Toymods Club Secretary
Location:
Sydney
Registered:
May 2002
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Re: 1G-GTE Economy
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Tue, 23 July 2002 12:51
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I'm sure someone who owns one would be able to give you a more accurate indication, but from what I've heard they're actually pretty darn good!
try doing a search on the forums, 'cos from memory there was a thread on fuel economy a while ago which might give you some figures. 
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I supported Toymods
Toymods Club Secretary
Location:
Sydney
Registered:
May 2002
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Location:
Cabramatta, NSW
Registered:
May 2002
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 Re: 1G-GTE Economy
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Tue, 23 July 2002 23:59
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As I wrote here:
| Nark wrote on Sun, 19 May 2002 7:43 PM |
10.7L/100 around town.
7.1L/100 on the freeway.
The 21R-C used to guzzle 13-14L/100km in City driving and produced a third the power... 
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Location:
Melbourne
Registered:
May 2002
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Re: 1G-GTE Economy
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Fri, 26 July 2002 09:34
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I dont think me and stradlater would really need to worry bout such things with our 1g-gte's as we are both gonna run them on gas.
lol
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Location:
Perth
Registered:
June 2002
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Re: 1G-GTE Economy
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Fri, 26 July 2002 09:44
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Is there any performance difference between running on normal fuel(unleaded etc) and LPG?
And how much does it cost to convert?
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Location:
Melbourne
Registered:
May 2002
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Re: 1G-GTE Economy
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Sat, 27 July 2002 10:04
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Well so im told the gas would give more performance than petrol, this is comming from a person who has built an eng running on gas capable of churning out 348kw at the treads. So i would take his word for it. As for conversion costs, hmm depends on your application, but for what me and stradlater r doin, look at about $3000 for the gas system, which includes everything, and dyno tunning of the ignition computer you choose to run.
Hope that helps
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Location:
Melbourne
Registered:
June 2002
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Re: 1G-GTE Economy
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Sat, 27 July 2002 12:38
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as far as i know, gas tends to burn more than it explodes, and since you want the fuel to explode, this means you would get less power...
thats probably a really bad explanation, but i'm pretty sure that gas gives you less power than petrol.
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Location:
Melbourne
Registered:
May 2002
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Re: 1G-GTE Economy
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Sat, 27 July 2002 13:31
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| Cory wrote on Sat, 27 July 2002 10:38 PM |
as far as i know, gas tends to burn more than it explodes, and since you want the fuel to explode, this means you would get less power...
thats probably a really bad explanation, but i'm pretty sure that gas gives you less power than petrol.
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if fuel exploded its called detonation, LPG does not "explode" as much as fuel as it has higher octaine rateing thus LPG is better
BUT a given volume LPG have 19% less power producing then the same volume of unleaded BUT this can be overcome by geting 19% more in there via higher boost/compression aswell as useing the higher octaine rateing then you still have the fact its a gasious fuel that mixs better with the air and its also cleaner burning ohh and its 1/2 the price.
Allan
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Location:
Melbourne
Registered:
June 2002
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Re: 1G-GTE Economy
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Sun, 28 July 2002 01:45
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i'm pretty sure the fuel would have to explode in some way...
if the fuel is just burning then how is it pushing the piston back down? something burning doesnt produce any force to push the piston down, like an explosion does.
the reason that petrol was originally used for engines was because of its explosive qualities (something like 100 or 1000 times more powerful than gunpowder).
thats what i leant in year 10 science anyway.
and isn't the term 'detonation' just a shortening of 'pre-detonation' which tells you that the fuel is exploding before it should be.
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Location:
Melbourne
Registered:
May 2002
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Re: 1G-GTE Economy
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Sun, 28 July 2002 02:58
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Fella's i think you will find that no fuel explodes, an explosion is the produc of what happens when a fuel burns inside a enclosed and sealed space. Hence in a combustion engine fuel is burnt inside a combustion chameber, and the process of burning orgnic substances, realses the products CO2 and H20, hence the carbon dioxcide, is what pushes against the walls of the chamber causing an explosion, or as in a combustion engines case forcing the piston down and driving the engine.
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Location:
Melbourne
Registered:
May 2002
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Re: 1G-GTE Economy
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Sun, 28 July 2002 03:12
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And i think you will find the reason why a properly built gas engine can produce more power than a petrol eng can, because, one it has a higher octane level allowing you to offset the less potent burning potential of lpg by advancing the timming, and also gas is stored as a liquid in a motor vechle, and a normal temps it exists as a gas, so therefore using heat to convert it self to gas will be taken from the inlet manifold hence giving cooler charge air, and therefore more power.
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Location:
Montrose, VIC
Registered:
May 2002
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Re: 1G-GTE Economy
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Sun, 28 July 2002 04:36
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I run my 4ag turbo on gas, and cost and performance wise I would have to say I'm happy. The question of power/octane/volume/etc. has a few different parts to it, so heres a bit of what I know:
1. LPG is definately a higher octane than petrol, how much by depends on where it comes from. Auto LPG is made up mainly of a mixture of butane and propane. Propane has a higher octane than butane (about 112 RON for propane, 100 for butane), with the overall rating of the fuel depending on how the mix. In Australia, it can be as bad as 50/50, whereas other places like the UK can be lucky to get 100% propane.
2. LPG is a slower burning fuel than petrol. As a result, combustion cannot be as effective with massive revs, kind of like a diesel engine (only nowhere near as bad). The reason diesel engines don't rev too well is because the combustion is too slow, thereby making it absolutely useless. However, this slower combustion can have the advantage of producing a bit more torque at lower revs.
3. A lot of it depends on how its gotten in there! Most LPG systems mix the fuel with the air as a gas vapour. The fuel is passed through a vapouriser, which uses hot water from the cooling system to ensure the fuel is vapourised. Latent heat is the amount of energy absorbed in conversion of a substance from one state to another e.g. liquid to gas (remember, LPG is a liquid while in the tank as its under pressure) LPG has a higher latent heat than petrol, therefore if injected as a liquid into the air, will take more heat from the intake charge than petrol, always a great thing for turbos! By vapourising the fuel before mixing it with the air, this advantage is lost. Also, most LPG systems a pretty crude. They work on some kind of crude carburettor effect to mix the fuel and air, in whatever quantity happens to get there. This also means that there is an air restriction to get the fuel in there, just like a carby. Most LPG conversions meet emmisions standards by crude feedback processors that work by slightly altering fuel pressure with engine vacuum being modulated by a simple circuit connected to the oxygen sensor.
There are many other things relevant, but at the end of the day it comes down to not that the fuel is inferior, but the way its generally brought into the engine is!
I'm probably going to be doing an LPG 1G project sometime in the next couple of months, just to get an old celica I've got going again.
I used LPG on my ae86 for a couple of reasons, namely that I had already converted the car about 12 months before (cost me $500 for the parts, $50 for the compliance) therefore the tank etc. was already in place. Also, cost. I used a Gasresearch LPG system, which only cost me about $500 to buy, and a haltech IG5 for the ignition. This definately cost a lot less to install and tune than an aftermarket management system ($?), as well as fuel pump, bigger injectors, etc.
I seem to have rambled on now don't I 
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Location:
Montrose, VIC
Registered:
May 2002
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Re: 1G-GTE Economy
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Sun, 28 July 2002 04:43
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Oh yeah, and forgot one other thing... Fuel prices! I like to drive my car like I'm sure it likes to be driven at times, and when I do this the fuel consumption can be a bit harsh (like any car thats being thrashed!) At least at 32c/litre (it was a lot better at 16... but *don't get me mad*) I can afford to stick $10 in the tank and that will give me a couple of hours entertainment. $10 of petrol? that usually only just gets me a couple of hours of pizza delivering in the 4K powered beast 
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Location:
Melbourne
Registered:
May 2002
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Re: 1G-GTE Economy
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Sun, 28 July 2002 05:08
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will be nice when IMPCO's LPG injector system becomes affordable!
Allan
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Location:
Montrose, VIC
Registered:
May 2002
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Re: 1G-GTE Economy
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Sun, 28 July 2002 12:40
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...or any of several other injection systems they keep on promising us. I sure as hell hope to have something on my UZ powered project! (which'll hopefully be an absolute monster when I can finally afford it)
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