My R34 Gtt Lpg Skyline

[urtwhistle]

HELLO EVERY BODY,

just thought i would post some info on my r34 gtt four door that i converted to lpg injection.

it runs a power fc, piggy backed by a prins gas ecu. which drives 6 gas injectors (hopefully 12 soon)

i have a 50lt tank in the spare wheel well which gives me 370k's at 70c a lt @ 100+ octane.

the only problem with gas (in a street car) is that a LEGAL gas tank is limited to about 300kw max.

i have attached a pdf of my car when it was dynoed, it shows both the gas and ultimate 98 graphs as it is dual fueled, if it was dedicated gas it would be alot better.

shane @ force fed gas in cockburn perth installed the system http://www.forcefedgas.com.au/. Great bloke great service, we both learnt alot from the install.

since installing the set up i have done about 5-7000 klm's and would deffinitly spend the $5000 again esp since we get $3000 back from the government.

regards

chris

drags07.pdf

dyno.pdf

[Dale FZ1]

There's been talk on and off about running LPG in a Skyline but you're the first bloke I've seen who's done it. The results look quite good. Congratulations

Couple of things I have to ask-

running stock turbo and boost?

the AFR settings on petrol and LPG look no different. I'd have thought you would need different fueling strategies to get the best from gas?

why not ditch the petrol system and run dedicated gas?

cheers

[Simon-S14]

looks great! im a LPG fitter also and have been thinking about doing it for a while to one of my cars. The vapor injection is the way to go, there is no restriction in the air stream like there is with a typical old school venturi system, the injection system has a standalone ECU which is easily mappable (the stuff we use is made by Zavoili) therefore there is no real benifit to running standalone gas! Thats the good thing about this system as you are able to get the same if not more power on LPG as you would on petrol.

No point ditching the petrol side of things as the tordial tank is only 50L which wont give you huge range.

You able to take the engine covers off for some more pics mate?

[Dale FZ1]

So does this second ECU control only fuel, or fuel + ignition?

I'd have thought that while you can get optimal fuel mapping, to get the best from a fuel that has extra anti-knock properties and aids in charge cooling, the ignition map would be advanced quite a bit further?

I find this interesting, would like to hear more.

[Simon-S14]

The system we use has Fuel only mapping, However what i thought about doing was with a remapped ECu was having duel maps, one for fuel and the other for LPG with revised ignition maps as you suggested.

if you cant do this, then yeah thats the only benifit of going LPG only. so that you can tune it 100% to suit.

I too am interested in seeing more results of LPG on forced motors. the only things ive been doing are LS1's, BF fords, rollas, camrys etc etc, nothing exciting.

[The Mafia]

looking on my wideband sensor - I think Gas likes to be about 6:1, I'm most likely wrong though. Check it out.

Edited January 13, 2008 by The Mafia

[urtwhistle]

There's been talk on and off about running LPG in a Skyline but you're the first bloke I've seen who's done it. The results look quite good. Congratulations

Couple of things I have to ask-

running stock turbo and boost?

the AFR settings on petrol and LPG look no different. I'd have thought you would need different fueling strategies to get the best from gas?

why not ditch the petrol system and run dedicated gas?

cheers

yep stock turbo ATM going a high flow once i can afford it. running 14psi

yeah sorry i just realised that i didnt put the right dyno sheet up. i gotta scan the gas 1. but the gas 1 is vertualy the same just on a much hotter day.

looks great! im a LPG fitter also and have been thinking about doing it for a while to one of my cars. The vapor injection is the way to go, there is no restriction in the air stream like there is with a typical old school venturi system, the injection system has a standalone ECU which is easily mappable (the stuff we use is made by Zavoili) therefore there is no real benifit to running standalone gas! Thats the good thing about this system as you are able to get the same if not more power on LPG as you would on petrol.

No point ditching the petrol side of things as the tordial tank is only 50L which wont give you huge range.

You able to take the engine covers off for some more pics mate?

i got 370 k's out of a tank which was preeety good. i'll get you a photo, shortly

So does this second ECU control only fuel, or fuel + ignition?

I'd have thought that while you can get optimal fuel mapping, to get the best from a fuel that has extra anti-knock properties and aids in charge cooling, the ignition map would be advanced quite a bit further?

I find this interesting, would like to hear more.

the prins ecu piggy backs the power fc and cuts power to the petrol injectors alters the fuel map slightly. what i got done was do a realy aggressive tune on petrol which brings the gas tune preety good but not perfect. but none the less its preety damn good.

[shnaped_second]

Interesting thread, what were you doing to get a 18.7? lol but the 13.9 on gas is kool

[urtwhistle]

Interesting thread, what were you doing to get a 18.7? lol but the 13.9 on gas is kool

HHAHHAHA lets just say driver error struggling with going from 1st to 2nd so i just putted down in 3rd

[RS4StagMan]

the only problem with gas (in a street car) is that a LEGAL gas tank is limited to about 300kw max.

Hi, I like your setup. And congratulations on the conversion.

I have a R34 Series 2 Stagea that runs on dedicated LPG....same motor as yours, although different type of system...Gas Research, not injection like yours.

Interested in a few things;

a) How is the power restricted by the legalities of the gas tank? Gas flow?

b) How much timing advance did the motor seem to be able to take throughout the rev range? I assume this is controlled by the Power FC alone?

c) What does the LPG dyno run look like? A/F ratios?

d) Any issue with cold starts? Does it start on petrol then change over to LPG automatically?

e) Any other mods to the car?

f) Do you get the same boost response/lag from LPG as petrol?

g) 14 PSI Boost is that about the limit for the stock turbo on the Neo?

Sorry for all the questions but I would like to know more as this is a very interesting topic for me... I'm yet to run mine on the dyno....it's only been recently converted and results seem pretty good....tuner expects equal or better power on LPG than petrol.

[fEkuaR]

Congratulations on the conversion, good stuff

[urtwhistle]

a) How is the power restricted by the legalities of the gas tank? Gas flow?

too my limited knoledge a SINGLE LEGAL TANK is limited to about 300kw. as any more flow and the tank lock off valves think the tank has ruptured and automaticly shut the thing down

b) How much timing advance did the motor seem to be able to take throughout the rev range? I assume this is controlled by the Power FC alone?

id imagaion it would be able to take alot more but as my car is dual fueled its limited to an aggressive tune for bp ultimate 98

c) What does the LPG dyno run look like? A/F ratios?

i'll try put them on when i get a chance to scan them. they are practicaly the same as the petrol just slightly more fuely and a little less tidy because of the gas set up being a tiny tiny bit delayed to the petrol ecu.

d) Any issue with cold starts? Does it start on petrol then change over to LPG automatically?

no issues with cold starts as it starts on petrol and flicks to gas once the water temp is 30+ deg, the change over is slightly staged as in it turns 1 gas injector on and turns 1 petrol injector off at a time.

e) Any other mods to the car?

not much yet only jic coil overs (rediculasly hard (they came on the car)) camber adjusters. soon my stereo will go in and the battery will be boot mounted.

therefore all the gas shite can be mounted were the battery was, then a front facing plenum, fmic and highflow.

f) Do you get the same boost response/lag from LPG as petrol?

every thing is identical, if your sitting at idle and put it straight to WOT it has a slight hesitation as the gas computer doesnt like it. but apparently prins is bringing out a new MAP attachment which should stop that.

g) 14 PSI Boost is that about the limit for the stock turbo on the Neo?

yeah i heard its a bit high, if it pops it will force me into high flowing it.

dont worry bout the questions, i wouldnt have posted it if i wasnt gonna answer them lol

i love being able to drive my turbo skyline for 700 odd k's with out seeing a servo. and the oil is soooo much cleaner.

check out http://www.profire.com.au/ Brad the owner who is a legend has a R33 which runs his OWN ecu which he has designed. that runs dedicated gas.

awsome bloke extremely helpfull he will be able to help any 1 and point you in the right direction.

regards

chris barge

[stolen_s15]

Awesome news mate!

Great to see people doing something new and different. I'm watching to see how the future tuning goes, hoepfully this will be a real option that can also sustain increased performance.

Nick

[Simon-S14]

Regarding the tank its possible to get higher rated Excess flow valves fitted to the tank, and still be legal. obviously this needs to be ordered in and fitted by a gas fitter. Then you'll have more flow available.

[urtwhistle]

Regarding the tank its possible to get higher rated Excess flow valves fitted to the tank, and still be legal. obviously this needs to be ordered in and fitted by a gas fitter. Then you'll have more flow available.

hmmm thats good to know simon.

the last 2 days i have had this annoying problem were on petrol the car drives perfect. but put it on gas the second you hit 4k rpm the car feels like you have hit a wall. it was driving me insane.

and then by accident when the car was idling i noticed the boost gage said 0 and i thought to my self shouldn't that be like -50 gazzilon cm3. turned out there was a broken vacume hose that went to the boost sensor. now my boost sensor works perfect and the gas works 10x better then b4 since the gas comuter/ converter were all tee'd into the same lot of vacume hoses on gas it builds booost soo much faster now. so happy it only took me 5 hourse after work looking and checking the wrong things lol.

regards

chris

[vidospace]

100 octane for 70c huh! Fantastic!

[RS4StagMan]

http://www.profire.com.au/[/url] Brad the owner who is a legend has a R33 which runs his OWN ecu which he has designed. that runs dedicated gas.

awsome bloke extremely helpfull he will be able to help any 1 and point you in the right direction.

regards

chris barge

Yes, the Profire system looks really good. It would be great when this finally becomes available...seems like still in development at the moment. Should really get some great results with that dedicated LPG ECU, although the payback on the system may be a few years considering it will cost a lot to fit and tune....

As a side note, I dropped into my installers workshop today and he had a early late 80's Toyota Soarer in there which has just been converted to dedicated LPG...had a later Soarer motor in it 2.5 litre single turbo conversion with the Gas Research system. Was dyno'ed at around 250 RW/KW on 18psi boost!

[chuckie]

G`DAY LAD`S,I had a chat with the lad`s FFG(force fed gas)with regard to going to dedicated gas system,ONE thing that iam looking for is a better tank set.One problem with the Stagea is all the shit around the current tank set up,i would like to pull spare wheel floor out & put flat setup in (will be looking into this big time)with the hope that i would be able to put best size tank`s in.cost is going to be a BIG issue ???.I will be going into have a look at some of the tank system`s they currently using so i will take some photo`s,Hope to have them get Stagea up on the hoist & have a good look around it so we can look at some sort of system setup,Hope to have some good info next week.cheer`s chuckie

[RS4StagMan]

The LPG tank setup I have in my Series 2 Stagea is a manifold pack (3 smaller round tanks all connected up) and looks like one rectangular tank under the car.

I didn't want to put my tank in the wagon space and we looked at using the spare wheel well but wasn't deep enough for a 'torodial' round LPG tank (space saver tyre).

In the end seeing as I was going dedicated LPG setup anyway, we removed the petrol tank and my manifold pack tank (about 59 litres usable) fit in perfectly in the same location (not too low) and even used the same fixing points as the petrol tank.

The LPG tank was then covered with black sheetmetal all round and looks like an Torana A9X 'Bathurst' style drop tank. All in all quite a neat setup.

There's probably heaps more options available...Chuckie are you going dual fuel or dedicated LPG?

[dmr]

congratulations on the conversion!

looks like we might start a trend here