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RB30 - is it worth building performance but running straight LPG?

Matty 31

By Matty 31,
in Engines & Forced Induction

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Matty 31 Grand Master

Matty 31

Posted
Posted

Hey guys

need some opinions. eventually in my R31 i want to run an RB20DET on straight gas, but i cant afford the new motor at the moment (as ive just spent 800 bucks gettin the head re-machined after a blown gasket - ouch). I am considering having the standard RB30 built for straight gas operation (ie pissing off the whole fuel system, gettin a bigger tank, removing the fuel tank and puttin the gas tank under the boot floor). Any ideas if this has been done yet, and if it is a good idea to do. I know i have to get brass valves and shit like that so it doesnt stuff up majorly, but im tryin to get rough pricing ideas cos no-one in adelaide wants to take me too seriously. i mean, they're more interested in poxy s13 silvias than a sleeper lookin 6 that could have a stomper of a motor underneath it (i apologise to any decent silvia owners).

Anyone who can help let me know

Matty T

SKY031 Grand Master

SKY031

Posted
Posted

If you're going to do it, it's worth doing a bit of research.

If it's done properly, you'll be very happy with the result, if it's done on the cheap, things will start to fall apart.

Check out gas research kits.

The most important thing in a gas only system is proper lubrication.

As far as octane goes, LPG is around 110 octane. Regular petrol 92(ish) octane and PULP 95(ish) octane

Cubes Grand Master

Cubes

Posted
Posted

I had a VS V8 Commodore that towards the end was getting real heavy on petrol due to mods. I looked in to supercharging it as cams in the ol' 5ltr really do stuff all and use too much petrol.

I looked in to an EFI gas setup that used LPG Gas injectors. I also looked in to the gas research carbs which was cheaper but didn't yield as good results as the gas injectors.

The RB30 with a high comp 9.5:1, the twin cam head, a nice GT30 turbo would get it moving very very nicely on gas.

Matty 31 Grand Master

Matty 31

Posted
  • Author
Posted

Cheers for the info so far guys...........Its good to know that i can get some people out there who take me seriously. Its almost the way to go now, my biggest thing will be is if i have to do anything to the ECU or not

  • 3 weeks later...
NFS Enthusiast

NFS

Posted
Posted

No you won't have to do anything to the ECU. Usually you have seperate gas computers and the switch that will switch from Gas to Petrol (or the other way around), but that's about all the electronics involved in a gas system. I've probably missed something out so someone correct me.

StuiE Rising Star

StuiE

Posted
Posted

AFAIK a dedicated gas system is better that dual fuel, since there is a compromise on both fuels making less power etc.

Saw a RX3 or something in a mag that ran LPG, apparantly the exhaust ran really hot and it was always buring holes in it...or do rotors have a hotter exhaust temp anyway?

NFS Enthusiast

NFS

Posted
Posted
a lot of work, and for what gain?

There isn't too much work, i've helped do a LPG conversion and it isn't very hard at all just gotta get a mechanic or something to fit the tank and lines properly. Also gains would be cheaper gas prices!! also the EPA say that any car running straight gas is 100% under emissions, so there will be less trouble from them!

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