VE II straight gas engine

[DAJOKER]

The 3.6L V6 factory LPG in the series II has a power output of 180....why is it not as powerful as the SV6's LLT / LFX at 210, if gas has a higher octane rating (yes you use more if it).

Even the Omega Series II factory gas has the 3.6L, compared to the SIDI LF1 3.0L petrol.

Is the factory gas engine in question, the old alloytec? which had a power output of 180 (the non highout put)

 

[_R_J_K_]

Probably mostly economy tuning to be honest. At a guess maybe Holden didn't want to make it look like it was chewing through fuel given that the kinds of people who would buy it initially would be people looking for cheap fuel instead of power figures. Don't have anything to compare it too given that only Holden used the LWR.

Would be extremely interested to see what could be done with tuning, engine specs (compression etc...) are pretty similar to the EcoLPi Barra, but the LPi Barra makes more power than its petrol version. Barra also uses liquid injection though versus the vapour injection used on the LWR which would probable make some kind of noticeable difference.

 

[DAJOKER]

There was also a massive compression ratio difference between the Falcon Lpi and Petrol engines, which I read somewhere really made the petrol engines lose a lot of the efficiency that comes with LPG and also the power because the lower compression petrol engine can't squeeze the LPG as much.

The compression ratio's for the falcon were 10.7 for the petrol and 12.5 for the Lpi engine.

However the compression ratio difference between the Commodore dedicated LPG and petrol engine seems minimal. 11.5 for the SIDI 3.6 petrol and 12.2 for the dedicated LPG.

Seriously thinking about converting my SIDI SV6 to dedicated gas, and hopefully taking advantage of the possible increase in power. Mines not really about saving money per/L.....its about a bit more power. Most people spent $5000 on engine mods and do this and that.....my engine mods might just be the LPG change over.

Does anyone know if you change to a dedicated LPG system, if the fuel tank can be taken out and replaced with what have been the factory LPG tank under the car, not in the boot.

 

[_R_J_K_]

Seriously thinking about converting my SIDI SV6 to dedicated gas, and hopefully taking advantage of the possible increase in power. Mines not really about saving money per/L.....its about a bit more power. Most people spent $5000 on engine mods and do this and that.....my engine mods might just be the LPG change over.

If you're gonna go down this path make sure you get somebody that can actually tune the thing for you (like a gas tuner that can get it on a dyno, not just an installer), otherwise you're just going to get the stock LPG equivalent. IMHO opinion it's pretty poor performance per dollar if you're just after "a bit" more power, you'd be far better off getting it tuned on petrol or looking at a flex tune, a bunch of factory ECUs are capable of it.

 

[Taranaki]

Less energy in LPG. The higher octane rating (slow burning) allows more advance, so you gain torque at lower RPM. So the maximum torque is about the same as petrol engine.
But the LPG engines seem to fade away above about 4000 RPM, hence the lower peak horsepower.