Tuning LPG

[Screwy]

guys,

have just converted the 308 in the patrol to straight gas twin tanks.
I know there is a mixture screw on top of the mixer, but is there anyother way to tune it?
There is no carbi.

I ask this cause its reving really high and i want to get it running well.

cheers,

screwy

[V8Patrol]

looking down at the mixer there "should be" a small bolt ( 3/8 ) right smack bang in the middle of the mixer.......
remove that bolt and underneath it there is a blade screw type bolt sitting about an inch from the top. This screw adjusts your idle.


Looking at where the big black hose from the converter joins the mixer.... well right next to where that hose finishes there is a adjusting piece on the side..... it should have the letters "L" & "R" and corrosponding arrows.
The "L" means lean
The "R" means rich

use a 4" shifter to adjust it as required keeping in mind that this really only controls the fuel flow for higher revs ( open road crusing etc)

Kingy

p/s
check for airleaks............... then check for airleaks again !

[high n mighty]

p/s
check for airleaks............... then check for airleaks again !

I think I would be alot more worried about GAS LEAKS

[Screwy]

looking down at the mixer there "should be" a small bolt ( 3/8 ) right smack bang in the middle of the mixer.......
remove that bolt and underneath it there is a blade screw type bolt sitting about an inch from the top. This screw adjusts your idle.


Looking at where the big black hose from the converter joins the mixer.... well right next to where that hose finishes there is a adjusting piece on the side..... it should have the letters "L" & "R" and corrosponding arrows.
The "L" means lean
The "R" means rich

use a 4" shifter to adjust it as required keeping in mind that this really only controls the fuel flow for higher revs ( open road crusing etc)

Kingy

p/s
check for airleaks............... then check for airleaks again !

thanks kingy, ill try that out as well and see how i go. I havnt done a leak test yet but ill do it tomorrow,

screwy

[RaginRover]

thanks kingy, ill try that out as well and see how i go. I havnt done a leak test yet but ill do it tomorrow,

screwy

morning fresh in a squirter bottle is what you need


Tom

[Screwy]

Ive fixed the massive vacuum leak problems, and now i cant get it to start at all
wat to do?

screwy

[kc_ksom]

Screwy

It will help me if you tell me what converter your running, aswell as what gas carby setup you have as there are many different types..

With the twin tank set up your running!!, have you got 2 carby's running seperate feeds, or is this in line, and only for longer range...

If you say there is no carby, what is feeding your engine???

Casey

[RaginRover]

Ive fixed the massive vacuum leak problems, and now i cant get it to start at all
wat to do?

screwy

Had anymore luck with this ?

Tom

[Screwy]

ive managed to get it running now, it starts fairly well concidering it hasnt got a primer yet, it wont quite idle but its close ( hand throttle out about half a centimetre ). idles well when the throttle is out a touch.
Cant get it to tune up any better than that. But drives well enough so will take it into a tune shop.

With regards to my LPG setup. I have 2 tanks for range purposes, they run into a hydrostatic one way valve and through to the convertor. Its an Impco 300A along with the Mixer.

What i have done with the carbi replacement is i bought a 1 inch alloy spacer plate and got a "mixer bowl" alloy welded really well onto this. I took the bottom rotchester quadrajet butterflys off the carbi, sat that on the inlet manifold and bolted the spacer and mixer ontop. The rest of the mixer / air filter setup bolts up to this. straight forward really.

screwy

[kc_ksom]

Sorry Screwy

Iv'e had nothing to do with the impco converters and mixers, I know that this system can be so much better iyou put it in the bin....

For reliability, go sprint gas, its easy, no hasells, no fuss.
For power, go gas research..

Tunning of lpg can only be done on a dyno, idle, cruise, and open throtle response has to be adjusted, this is to make sure you are getting the correct air/fuel ratio, as to lean you are going to get hot, detonate, and blow the motor VERY FAST!!!
To rich and this will cause your bores to glaze, use oil, and have NO POWER..
Aswell as this, LPG runs better with a none vacum operated advance, remove this and set to about 10deg initial, if it pings bring it back, but a more inital advance helps. The vacume advance can be pulled off and tossed in the bin, or on ebay for $2...You can get your dizzy regraphed for a more agressive curve redone by an auto elec, this will give you good mid range torque, and a more progressive rpm climb..

As LPG takes up more space in the manifold, a single plane manifold is also an advantage, high rise even better, a tunnel ram NOW YOUR TALKIN, this is the reason why you will use more lpg to fuel.

Also try and get your converter as close to the Mixer as possible, this will help with keeping the gas in a better form going into the motor, because the gas gets hot it will turn to vapor, and will lose its detonation qualities, this is another reason why you use more gas.
Injected gas would be the go..
I hope this has helped.
Casey

[Screwy]

im very happy with the setup im running.
It only has to work and be effective.
If i want more power ill get a chev.
Not interested in gas research etc etc. Ill leave my setup as is.
Its more than enough to do the job.
Just needs a tune.

screwy

[kc_ksom]

No prob screwy, you asked the question, i was just trying to help.