i know there are posts but i cant find any.

but im wondering whats needed to get a gain from straight gas setups? ive got an ED duel fuel wagon and i can get a second tank and cradle for nothing but what else would i need and what do i need to do under the hood for real gains?

budget is a big thing too. its a small budget

I suggest a Gas only TB, like one from GRA.
Set base timing to suit.

Then enjoy.

remove the std intake manifold...customise the intake to suit a low restriction mixer like impco 425...

get the ecu ignition maps remaped to suit lpg

wont be cheap as there is limited support for the I6, so expect to pay$$$

else keep your std setup and just remove the tank...hey presto straight gas!!

Straight gas is the way to go. Dual fuel is usually a compromise with engine setup, different fuels like different tunes.
Ive got a ef wagon straight gas did the conversion myself. I ripped out the fuel tank, fuel lines & charcoal canister. The fuel rail & injectors went and I installed little welch plugs in the manifold.
Also changed the plugs one head range colder for the lpg went with the bp6ey ngk plugs.
When I did the head gasket I got 1mm machined off it to raise the compression to 10:1 which lpg really loves.
Im using an impco 225 mixer with std airvalve, b2 converter, pod filter. To help with the first start of the day I fitted a primer which connects straight off the primary port thru a regular petrol lock off solenoid connected then into some 6mm hose into an adapter into the secondary port of the converter. Ive got a little push button on the side of the steering column that i usually just hold in for 3 or 4 seconds then it starts in about 5 or 6 turns of the engine. Once the converter is up to temperature it starts almost instantly - quicker than a regular ef on petrol does anyway.
Also ripped out the original ecu and put an a tickford gas ecu from an ef ii, i think we managed an extra 2L per 100 with the ecu alone. it picks up some power too.
Im thinking about getting an lpg grind camshaft for it.

Luke111, what type of gas tank are you using?

And when you removed the tank did you just make up a plate to fill in the hole?

I have the scuba tank setup. I was wondering if I could mount a second scuba tank under the original if I took out the petrol tank.

BenJ

im using a a90 tank, apa. Ive run it completely dry once (had to get flat towed to the servo) and it took 68litres.
I used a 2-176ohm sender unit it so it uses the original fuel gauge. i ended up putting a 22ohm resistor in the wiring to make the distance to empty right.

I got a big plate cut out at a sheetmetal supplier. I used 3mm steel and sealed it up when I installed it. I just use that area for the jack, wheel brace, spare intake pipe etc.

I also removed the petrol filler neck and I cut out a piece of stainless steel 2mm to cover the hole.