Lpg Powered Gtr

[haw001]

Before going into details, I should preface this by saying there is no way that I am going to be talked out of it, it's already happening.

The car is a basically stock R32 GTR which is being road driven, not tracked at all. I've got other cars to do that with.

The system is a KME Akme, from all intents one of the best on the market and quite advanced in it's management, so no longer simply a burst of LPG pumped in. http://www.kme.com.pl/EN_autogaz1.html

This system is ecu controlled with single cylinder injection, same as with the standard petrol system. No injectors as LPG is already gas, but each cylinder has a seperate feed and it piggybacks on the standard injector signal, so the car can be tuned normally plus using the LPG ECU. The website has all the info.

My plan is to remove the petrol tank to make room for the gas cylinder and then add a small petrol tank for starting (the lpg doesn't cut in until the temperature reaches around 40 d c)

According to the manufacturer the unit is good to 260kw with single injector points, 350+ with multiple injectors per cylinder. I'm starting out with 1, but will allow room for 2 if necessary.

Install is underway. I'll post some picture tomorrow.

[cosmokram3r]

Interesting to see how this will turn out.. How much is the whole conversion costing in parts?

[Gtrgodzilla67]

About time im also converting my 340kw gtr to gas , running twin service lines and twin injectors, but im using a different system and im going to piggyback of the power fc,

Should be very interesting to see our results.

[joeyjoejoejuniorshabadoo]

will be watching this thread... wanna do similar on a dd at some stage

[Got Boost?]

Awesome! Can't wait to see results

[infamous_t]

Keep the gas tank in the boot, and remove the petrol one so you can run dual exhausts like the HKS Zero-R

[boostin_r33]

This will be very intresting in performance

[haw001]

Interesting thing that most people don't realise is that LPG has RON rating of 110, so in theory, a properly tuned system should have about 5-10% more power than on 98 RON petrol. I'll put it on the dyno for proper testing when done and proper tuning. The software comes with the system an no charge and the ecu plugs into a computer through a standard serial port. This will work with a Power FC as well.

I'm not putting the tank in the boot, even though the R32 has a natural spot between the wheel arches. I think the tanks look butt ugly in the boot and are one of the main detractors of the LPG system. Hopefully I'll still be able to keep a decent tank underneath, if a bit smaller than standard. Hopefully at least 50L + 10L of petrol. Will have to fill up more often, but not that bad.

[philvia]

i cant wait to see the results of this

good luck

[rtune]

Interesting thing that most people don't realise is that LPG has RON rating of 110, so in theory, a properly tuned system should have about 5-10% more power than on 98 RON petrol.

It might have a higher knock rating, but it has about 30% less calorific value per cubic mm, which (I think) is why lpg cars are down on torque vs petrol cars with everything else being equal.

So *if* you can increase the boost you make some of that back.

Petrol cools ("charge cooling") LPG gas doesnt (unless it is liquid injection. Which isn't available in australia yet). With an aggressive tune running rich combats knock. (Excess petrol = excess cooling). No cooling from LPG equals worse thermal efficiency which means down on power, or knocking. If the intake air isn't cold .. even more power loss.

I thought this post was interesting:

http://gasforum.dridders.de/read.php?4,76920,76969

and these guys have done a turbo or two:

http://www.go-lpg.co.uk/Turbo.html

but from reading them it seems like injector choice (not just size but speed of reaction) and being able to flow enough fuel is critical.

disclaimer: this is just from some time searching other posts elsewhere.

[im late]

I look forward to seeing your dyno results...

But more importantly, the "real world" day to day practicality and reliabilty with an RB26.

[slaughter]

i look forward to seeing a gtr fill up on GAS at the petrol station

[urtwhistle]

INTERESTING... shall be very interesting to see how much Gas flow you actualy get. as i went the Prins route and have maxed out my injectors at about 200rwkw.

R34nur, interesting you say that. i dynoed nearly exactly the same power figures on gas, but while at the drags i would get say 25 nock on petrol but 7-12 on LPG. will be great when more people get into this sort of thing, it will make searching for problems alot easier.

regards

Edited June 23, 2008 by urtwhistle

[SimonR32]

gas in gtr will be fun...

fill up your tank every 100-150kms

ive got better things to do than spend my life at petrol stations

[DRD-00F]

I am DEFINATELY going to be keeping an eye on this

[arep3]

Yeah ill be keepin an eye on this. very interesting. You'll hafta keep us all updated for a long time after the install. before and after dynos and your opinion. pros cons etc. id still like to know what its like in 6 months time.

[haw001]

Cerbera, kinda funny if you look at your post.

"...ive got better things to do than spend my life at petrol stations", then a BIG "Buy my GTR!" under it

A bit Ironic, kinda makes you wonder if the fuel costs are the reason for selling it.

[haw001]

Ok a few photos after about 4 hours of work. Doesn't look like much, but most of the hard stuff is done. Still have to solder in all the wires and plug in all the fuel lines, but it hasn't been too bad so far.

Injectors drilled and mounted.

Close up of injectors. Room for another, but would have to remove pressure bar to fit them.

Reducer fitted with mm to spare all round

Even clears the strut tower brace (just)

Gas gauge and switch, not yet mounted, but drilled.

For illustration, this is where I'm going to mount the injector rails. Will have to make a bracket as the injector loom is too flimsy.

[SLIPPERY]

i think he meant the lpg gtr will need to refill a lot more often than a petrol gtr due to the reasons given in the posts in this thread.

[haw001]

You can't see it in any of the photos, but all the wiring has been pulled through the firewall. I've opted to mount the ECU in cabin for esthetics and water protection. The ecu fits (jams) perfectly up in the driver side kick panel directly below the loom port. I used the loom port behind the driver side front wheel so no new holes were needed.

The only problem is that I've elected to take all the sensor feeds off the standard ecu and the wires are about 30 cm too short to reach the standard ecu so will need to be extended. There's a fair amount of extra cable in the engine bay loom, so I'm going to wire up all the engine bay stuff first, then possibly pull the cables back through and remount the LPG ecu somewhere closer to the standard ecu.