Today I tested the difference between SD and MAF mode both in open loop

[Dirk Diggler]

For the sake of avoiding OCD i decided to go back to MAF operation for sometime to see how i liked it and if there was any difference. To my surprise the number between the MAF and SD were within .5 HP of each other. Here is the dyno graph that shows the proof




The car was dialed in using SD mode first and then some WOT power runs were made. THe maf was then hooked up and dialed in (fule only no timing changes) and I made some WOT pull with the maf. The graph appears to be off by one HP but that is because the decimal placed were truncated. These numbers were aquired on a Mustang Dyno using the Dyno Jet simulation. Run 1 denotes SD operation and Run 2 is the MAF. Enjoy

[Delco]

Was the maf removed for the SD tune , I find the extra power we make is attributed to the removal of the resritction of the maf. Basically if the tune is right with x amount of fuel and y timing then the engine doesnt care how it is calculated .

[Bruce Melton]

I am no expert but not surprised either.
A MAF tune ought to work better on any given day other than tune day.. The MAF is the state of the art way of telling the engine what is different.
Thanks for the post.

[Dirk Diggler]

Was the maf removed for the SD tune , I find the extra power we make is attributed to the removal of the resritction of the maf. Basically if the tune is right with x amount of fuel and y timing then the engine doesnt care how it is calculated .

Yes the Maf was gone for the SD tune. When I finished the SD part of the tune I made some WOT pulls got a number and then put the maf into the system.