foxsl

iTrader: (1)

For an intake like the Halltech mf108, the company states "requires MAF recalibration to translate proper MAF transfer curves," are they just saying retune the maf?

Also, the Halltech mf103 states that no tuning is required, does the cable have some kind of resistor to trick the reading from the maf to ecu?

Thanks

ChopperDoc

MAF works by using a heated element inside the sensor using a 5v signal. What this means is that as air flows over the element, it requires more voltage (hertz in GM cars, same same) in order to maintain a certain predefined temperature.

What this means to you: Increasing the volume of air that travels through the sensor by "area" must be accounted for. Even though the sensor will read the airflow, the PCM has no idea how much air a particular voltage represents. The calculations will be off. We have to TELL it what the voltages represent in the table. Here is a picture of the actual table:




So yeah, I believe changing an intake qualifies for a MAF cal, at a minimum. Basically anything that changes airflow/fueling calculations after the sensor (post-metered air) like cams, injectors, new tubing, throttle bodies, etc... require MAF calibrations, and usually a lot more (tune). This doesn't apply to exhaust though because that's after the fact and doesn't change the fuel calcs, excluding trims of course.

foxsl

iTrader: (1)

Thanks for the detailed reply. I understand as I've tuned maf equipped setups before, my confusion here stems from how Halltech describes a form of tricking the maf signal to under-report air.
For sure any intake tract change requires a maf recalibration, however they're somehow saying you won't have to retune the maf curve with the 103 intake kit but do mention needing to recalibrate the maf for their larger 108 intake. I'm trying to get to the bottom of the in-between fine details of how they're pulling this 103 intake off without a maf recal.

VandykeT/A

The 103 probably has the same diameter tubing the sensor mounts in as stock and the 108 is larger. If the 103 is bigger than stock it probably comes with a tapered insert to adapt it down to stock diameter just before the sensor. I’ve seen some of the nnbs truck intakes have those.

ChopperDoc

Vandyke, are you a tuner or a troll? NO 103 is a LOT bigger than stock, by 25mm, typically. TSP sells a 4” MAF just for this mod... And for tubing, what are you talking about? Why even bother upgrading the size if you choke it at the MAF ring? The only exception would be the blade only MAF mods some guys fab in. But you’re talking stock, tube mount MAF assembly, somehow working with a 103 or 108? I guess you could install it inside the 103 piping though lol.

VandykeT/A

I’ve never measured a C6 stock intake tubing/ductwork whatever you want to call it but if it’s a card style maf and the intake diameter changes then the maf needs tuned. I’ve seen a few of the spectre intakes that had a small insert that tapered just before the maf.

ChopperDoc

Sorry man, I miss read your post. I was on my phone, and also thought you were someone else that was acting a fool the other day. Your name is similar lol. I thought you were him on about some more weird stuff lol. Yeah I agree, with card style any change to tubing/ducting size requires a MAF tune with that setup. I would also say, with any change a tune is highly recommended due to the difference in actual airflow.