Performance Mods for LPG

[VQXTC]

Hey all, I have a VL Commdore 5 speed manual.

Just wondering what performance mods can be done to a car that runs mainly on gas........
Yes it is dual fuel, but I only start it and let it run for at least 5 minutes on fuel in the morning then switch it to gas.......

Thanx for any info.........cheers

 

[Stewart1000]

well if you want to spend big bucks, LPG has a very high octane so that means you could run a high compression without causing damage like is would on petrol but that means you couldn't run it on petrol, ever.

also, if you want to run it on only gas, remove that cat converter as LPG doesnt have emissions that are compatible with the catalytic converter.

run a cold air induction system

probably sounds silly but if you dont run the car for very long on fuel just have 1/4 of the fuel tank full as its quite heave and will slow you down.

other that the usual, cam, exhaust, porting, bigger t/body, etc etc i am not sure what mainly benifits a motor runnign on lpg

 

[mag]

Hey all, I have a VL Commdore 5 speed manual.

Just wondering what performance mods can be done to a car that runs mainly on gas........
Yes it is dual fuel, but I only start it and let it run for at least 5 minutes on fuel in the morning then switch it to gas.......

Thanx for any info.........cheers

Cant think 4 a VL but must have ur spark plugs 1-2 grades colder than standard..

If u have NGK spark plugs that would be BCPR5ES-11.. The 11 on the end is the gap 1.1mm.

 

[mag]

Cant think 4 a VL but must have ur spark plugs 1-2 grades colder than standard..

If u have NGK spark plugs that would be BCPR5ES-11.. The 11 on the end is the gap 1.1mm.

Also real good spark plug leads and a better coil if u can get 1.
LPG is harder to ignite than petrol..:thumbsup:

 

[J_D]

Be good to do a turbo setup with a boost controller. Wind up the wik on LPG and down on petty.

 

[Stewart1000]

yes that comment on the spark plugs by mag was a good one.

try and get your hands on an aftermarked coil. Don't get those stupid spark plugs with the 4 tangs on the end, they dont create 4 sparks as some people think they do.
what the pros do is aim the spark plug, so that the back of the tang is facing the right hand side of the block and the open side is facing the majority of area in the head.
not sure if that makes sense...

 

[mag]

yes that comment on the spark plugs by mag was a good one.

try and get your hands on an aftermarked coil. Don't get those stupid spark plugs with the 4 tangs on the end, they dont create 4 sparks as some people think they do.
what the pros do is aim the spark plug, so that the back of the tang is facing the right hand side of the block and the open side is facing the majority of area in the head.
not sure if that makes sense...

Yeh that spark plug aiming is called spark plug indexing, ok if you've got some serious horse power..:thumbsup:

 

[Stewart1000]

yeah, not for the average person ay.

i have been thinking about the LPG performance situation...

you want to advance the timing, get the camshaft re-ground, you want as little overlap as possible, no overlap would be the best, not much lift, you want those valves shut as much as possible as you want alot of compression to make use of the octane, high voltage output coil. i dont know what sort of LPG system you are using, electronic injection, flow fed injection, vapor whatever. but if its not injection, think about upgrading to that if you want to have a powerfull car on gas