Gas conversion for VS commodore 5 sp Manual

[vscommodore]

Hey,
I am considering the gas conversion as the rebate will be taken off very soon. I have had a couple of quotes, all ranging from around $250 with the rebate
I have a 3.8L VS commodore 5 sp Manual. Would this make any difference to the problems associated to gas conversions? I have heard alot about automatics, just none about manuals.

I have been looking at other threads and people talk about vapour systems.What is involved in a vapour system, as this is the first I've heard of it before.
Thanks.

[German Statesman]

Don't convert this car to LPG - Holden advised against converting manual transmission V6 vehicles as far back as VN days, and we had to look after a fleet of 6 that belonged to a security firm that were endless problems...

Massive intake backfires are a daily event and three of the 6 mentioned above suffered engine damage as well including one backfire that made the engine run in reverse...:confused:

Auto yes, manual no way.

Cheers

J

[vscommodore]

Thankyou very much. I had just heard so much info on atuos that thought manuals may have been a bit better.

[PoweredByCNG]

Backfires are not caused by the transmission (manual vs. auto). They are caused mainly by poor ignition maintenance (spark plugs, leads, coils) or by lean air/fuel mixtures. If you religiously maintain your vehicle, servicing the gas system annually and keeping everything in tip-top order, you shouldn't have a problem.

Regards,
Dave

[German Statesman]

Backfires are not caused by the transmission (manual vs. auto). They are caused mainly by poor ignition maintenance (spark plugs, leads, coils) or by lean air/fuel mixtures. If you religiously maintain your vehicle, servicing the gas system annually and keeping everything in tip-top order, you shouldn't have a problem.

Regards,
Dave


I respectfully correct you on this...the previous V6 engine was a Buick-derived design not intended to have a manual transmission. When the engine deaccelerates, it doesn't have a graduated de-acceleration (no de-accelleration stepper motors or pintles e.g. Nissan), and the engine almost completely stalls until the TPS brings it back up again - when the clutch is re-engaged, the engine leans out the LPG fuel mixture and backfires. There is also a spark on the waste stroke of the ignition cycle on these engines which also complicates matters.

Refer to the Holden Service Bulletin on this matter from 1989, and reiterated every year from then on in subsequential Bulletin Annuals.

This does not apply to any other engine bar the Holden V6 engine mentioned...I do not know of any other manual transmission vehicle that cannot be converted to LPG.

BTW, this was also demonstrated on a dynamometer by us to QLD zone Holden dealer sales personnel in 1994 with spectacular (catastrophic) results.

[PoweredByCNG]

...
BTW, this was also demonstrated on a dynamometer by us to QLD zone Holden dealer sales personnel in 1994 with spectacular (catastrophic) results.

Interesting. I stand corrected then.

Still doesn't stop the determined from converting their manuals to SVI LPG though.

Regards,
Dave

[German Statesman]

No offence or bad vibes intended.

The liquid injection may indeed solve this problem but I'd think its early days yet.

Cheers

[vscommodore]

Well is it an option for me to convert the car to gas and try it out for myself. If it is a problem, is it OK for me to leave it on petrol forever and not ever touch LPG again? Or is there a ratio that needs to be met, that the LPG needs a certain amount of km's per week to flush the engine???