Thread: Why run a MAFF

The boosted guys he is talking about are LS1 guys. It's alot easier to convert them to a 3-bar speed denity tune custom OS. Our pcm's are only setup to go to 140kPa (~6psi), and you'd have to mess with a custom OS (doubt anyone's successfully done a 3800 with results yet... I was shown the space in the data on our pcm's, and there's not enough in the VE's current location to add many lines beyond stock, so alot of re-directing would be needed).

- Dave

The VE tuning is a stabilizer for the actual MAF tune. Along with being the table your car uses for the initial 30sec of start-up, it's also referenced during the rest of the time in the background of how the MAF tune is applied. Very good thing to have dialed in for best mpg results on cars with modded valvetrains or new power adders.

Again, just to be clear, there's a reason this isn't a regular topic for our application.

For the LSx folks, many of the N/A guys want to squeeze every inch of CFM into the engine, since it's being drawn in with less force & can mean 5% power gain in some cases. There's also the desire to not worry about outflowing the MAF table, which is something big N/A or F/I LSx's may be capable of doing. They aren't as willing to do an AFC-type of item to avoid this, when the speed density option is more common in their world.

The tune without a MAF isn't as quick to react to smaller airflow changes. It's great for WOT conditions, but lower RPM activity and weather differences are best adapted by the combination of the MAF and MAP calculating needed fuel. It takes tons of tuning to get it right on a MAP alone. Many 3800 folks don't even attempt VE tuning due to the large amount of time it can take to dial in the entire used range of the table.

- Dave