Sd Or Maf Tune?

[.justin.]

then answer me this. why do you need to have a perfect VE then before enabling the maf? your vehicle is SD when doing all tuning and maf is there to help make for small adjustments. SD been around in racing way before maf systems. they swapped to maf systems for faster corrections to everyday driving and to aid in mods. also look at this way once a maf fails it goes into SD mode

You don't have to have a perfect VE table. MAF is FAR more important in the final airflow calculation than the VE table is. Want proof? Go out and make a 20% adjustment to the VE table and see what happens to AFR or trims. Set that back to stock and make a 20% change to the MAF calibration. See which one has the greater impact.

[zippy]

With the weather conditions that you have to deal with, I'd go with a maf on there. I don't know how much of the year you drive it, but I know that if your weather is anything like around here you'll go from 0º to 100º in temperature range. Maf systems tend to work very well in wide temperature ranges. SD tuning is great and for most applications like yours it is the way to go. The problem is that SD tuning takes a considerable amount of time to get tuned in and depending on weather may need changes occasionally. Most guys running boosted applications and SD will have more than 40 hours of logging and tuning time into their setup before they are happy with it. You'll deffinitly want to go with a 2 bar system. The maf would be a restriction which is a down side. The gain to having it on there will be in the times that you are simply street driving the truck under normal traffic driving conditions. Obviously any time you are going to be into the throttle hard you'll be maxing the maf's airflow reading ability. Helping tune a friends VHO, he is maxing his maf at 4100rpm on his 370 and until his intake system got oil soaked from a faulty crankcase ventilation setup his drivability was great without much effect to wide open tuning. As for the aftermarket, they've been running speed density because there aren't alot of maf sensors out there big enough to match their system. They would also have to build a much more complicated system to run maf sensors on aftermarket systems. More complicated means more expense and less buyers. The other reason it's not needed in the aftermarket world is that anyone buying an aftermarket injection system doesn't likely ever stop tuning on them. Laptops become as common as a cd player in cars with aftermarket injection systems.