LsF-150

iTrader: (2)

IMO Yes, a lot of people will tell you a "properly" tuned ve table will get the same mileage. The progression by oem from carb>sd tbi>sd multi port>to maf tells me which is better. When I added the turbo set up to my truck the two main things that changed were 1 full point reduction in compression, 10.5:1 to 9.5:1 and 2 bar sd and my mileage (out of boost) went to ****. 19 highway went to 14 and around town is single digits. I've been all over the truck and am convinced losing the maf is the culprit.

redtan

iTrader: (5)

First of all, not all "OEMs" run MAFs, so just because it's the most recent doesn't mean it's better. And OEMs use MAFs more because of adjust-ability and ease of tuning than because they get better mileage.

What proof do you have that a properly setup SD tune will get worse gas mileage than a similar tune utilizing a MAF?

You increase the weight of the truck, add boost, lower compression significantly and you blame fuel efficiency on the SD tune...? You have much to learn.

xRelapse13

iTrader: (21)

Most likely the culprit is in the tune. Could be improper injector data leading to rich transitional fueling, low timing at cruise areas, richer idle, richer cruise, too aggressive of a transition to PE, etc.

Also, a properly tuned SD set up will not have worse mileage than a MAF tune. GM uses a hybrid of both from the factory. They're just different ways to control the fueling, if the fueling is correct for the amount of airflow the engine is flowing than efficiency is just a matter of engine capability. All that of course goes out the window though if it's a shoddy tune.

vwdave

iTrader: (3)

As a matter of fact VW in the last few years went away from MAF's again and went back to SD.