LPG Discussion Forum

Just watched the video and subscribed, my first YouTube subscription.

Looks great! Don't think I've seen much of the cockpit before.

Matrix connector to Superseal connector adapter looms are/were available.

I was typing on my phone last post so kept it brief.

There's no real difference in design that could cause solenoids on VSI reducers to get caked up with crud more than other types so I think the difference is probably that the solenoids get hotter on VSI's due to the position they're fitted on ...

I'm surprised that solenoid wasn't working, they're usually fairly gunged up if it's bad enough not to work.

It is usually the solenoids that get stuck closed by heavy ends, particularly on VSI reducers. But they also seem to be more prone to getting gummed up with the same inside than most other reducers.

The leak is from the air filter housing. Since any MAF would be downstream towards the engine from the air filter housing the leak in your video wouldn't affect any MAF readings and isn't a vacuum leak, it is just a leak on the air filter housing which at worst might mean a small minority of air the ...

Usually road tax is the same or cheaper after LPG conversion.

I've never heard of anyone's road tax increasing in price due to LPG conversion and that makes no sense at all.

Installers like myself never used to mention the slightly cheaper road tax after LPG conversion, it was only around £10 ...

Vacuum leaks on an engine with Maf sensor are more likely to lead to problems than vac leaks on engines with map sensors. On the Maf setup the Maf reads less airflow, which can make fuel trims more positive and/or cause which LTFT is applied/used (but less of the 'or', more of the 'and'). On the Map ...

Is your reducer leaking gas into the inlet manifold by the vacuum connection tube?

Some injector designs will output quite a lot of gas even with small nozzles even if only pulsed for a very short ginj.. the internal design might have a slow closing time and/or a wide and long output shaft before ...

TBH I don't see many mixer systems these days but they changed over the years.

The older ones seemed to be more sensitive in that you could probably get away with fitting a slightly wider venturi mixer (compared to a newer one), set the sensitivity screw so it was sensitive and it could still be ...

When you start most petrol cars from cold you might be able to smell petrol, the choke effect / excess fuel factor means some petrol comes out of the exhaust.

The pipes between LPG injectors and manifold might be too long, this can explain some lumpiness when changing from petrol to LPG. Or it ...

You could calibrate it so STFT+LTFT = 0 (or close to 0) when running on LPG. But there can be problems doing that... For starters, as you already know it can make for more of a change when you switch between fuels. The bigger that change is the longer the engine runs with slightly incorrect mixture ...

To keep it simple just set reference pressure to the pressure reading at idle. Then calibrate. If you change the referece pressure you need to do most of the calibration again because of that pressure compensation I discussed in detail. Also to keep it simple for now just set minimum (switch back to ...

Yes the pressure setting in your screenshot above is the set reference pressure.

In most 'screens' in your LPG software you can see LPG pressure and manifold pressure. The LPG pressure reading is LPG pressure above manifold pressure, not absolute pressure. The manifold pressure reading is absolute ...

just out of interest simon , but , why not a mixer ring and a r90 ?


The Impco gas carb setups are a lot less fiddly to set up correctly than a mixer setup, especially with today's R90's which are not quite what they used to be. They're also more lkely to be reliable and allow consistent ...

You could see pressure fluctuating between 1.4 and 2.2 bar if you keep your foot down and pressure remains at 1.4 bar above manifold pressure then you suddenly lift off the throttle... Foot down will see manifold pressure same as atmospheric pressure, LPG pressure is relative to manifold pressure so ...

When the engine is fully warmed up and idling on LPG, what is Ginj (gas injector pulse duration) and Pinj (petrol injector pulse duration)?

A potential issue with fitting nozzles that are too big can be due to it meaning Ginj has to be shorter, the injectors are linear from around a certain Ginj ...

I had a 1972 converted. 350 CI straight propane. Great truck and great engine to convert. Two comments on your truck. It may be an illusion but the regulator looks very close to the exhaust. That would not be allowed in Canada. Minimum of 8 inches (about 20 centimeters required here). Secondly, a ...

You know it makes sense to investigate the whistling sound, it could be a vacuum leak, a vacuum leak could be in a troublesome position such as on the threads of a 'spud' (brass LPG injection nozzle) in the manifold potentially making one cylinder run leaner than others. But if the whistling only ...

Could be that the recent new reducer is outputting a different pressure to the old one. I don't know if your reducer is BRC, BRC reducers usually come preset at close to either 1.2 or 1.5 bar, the pressure can be ajusted by turning an allen socket but you won't be able to read the pressure or know ...