Dodge Ram 2500 Diesel fuel injectors

If he's going by the overhead, he's fooling himself. The 275 RV injectors have a larger opening, and deliver more fuel for the same amount of 'ON' time as the stock injectors. This develops more power, and therefore less 'ON' time is needed for the same power output as the stock injectors.

The computer has no way of measuring the fuel flow through the injectors - it knows that at a certain RPM, and a certain amount of 'ON' time will deliver a certain amount of fuel. It uses those assumptions to calculate fuel economy.

Miles travelled per tank of fuel is the only reliable way to calculate fuel economy, and then only if you fill to the same level each time.

Don't trust the overhead computer readout. Mine is 1.5 miles per gallon off. The real test is the old fashion way of using your brain and calculating the mileage.

While I can't speak for a Dodge, the readout on my Duramax is also off slightly compared to my actual calculations, but it's consistent. While it may not give dead on numbers, it's easy to see trends. I think it would be close enough to show an increase from 19 -> 25, although in reality it may be 17.5 -> 23.5.

Does the Doge have an "instant" mpg readout?

DJ

As said by Tom L, if you change the injectors with ones with a different flow rating from the originals, the mileage readings from the trip computer are now meaningless.

I think you mean "even more meaningless" right?

Actually, I am impressed on how close many of them are considering that it is all done by pure calculation but you are correct, even more meaningless :-)