High vaccum or BSFC for more mileage

[vijay]

Hi ecomodder's,
I have Fiat palio 1.6 16V 5 door (Stilo in other part of the world). In city with decent light throttle I am getting 8.5 kmpl with A/C on. After reading some articles on BSFC, I tried upshifting gears in the pattern 1-3-5 quickly and throttle position was around 50~75% for a fairly long time ~5 secs. Initial rpm in 5th gear @1000rpm and the car vibrates. Do we have real gain in FE compared to another method : light throttle(High vaccum) and keeping in low gear around 2K rpm and shift inside 2K rpm. Which method yields more mileage.
Also in HHO forums its mentioned as MAP sensor enhancer. Its simple resistor lowers the MAP voltage. AFAIK voltage increases with increase in pressure. If we reduce the voltage which means there is some vaccum. But as per the BSFC chart engine is more efficient at higher pressures. How do we get more mileage by altering the MAP.

Cheers.

[piers.singer]

High vacuum is good for cruising and DWL whilst getting the most out of your car's BSFC is good for P&G. In an ideal world, P&G-ing everywhere would give you the best FE, however the practical realities mean that it isn't always possible. Therefore you should learn both when to DWL and when to P&G.

If your car is juddering/vibrating then you're shifting too early. This will increase engine load and spoil your fuel economy.

[vijay]

Thanks. Currently the rpm drops to 1000 after upshifting. I will increase to 1.5K's and check for juddering. In P&G once the desire speed is reached do I need to put in neutral and coast or simply pull off the accelerator then apply 50~75% throttle.

[California98Civic]

Originally Posted by vijay

Thanks. Currently the rpm drops to 1000 after upshifting. I will increase to 1.5K's and check for juddering. In P&G once the desire speed is reached do I need to put in neutral and coast or simply pull off the accelerator then apply 50~75% throttle.

Put the clutch in and glide. If conditions are safe enough, cut the injectors and leave the ignition in the run position. Bump start in fifth gear--even down to 15 or 20 mph.