Was wondering if someone could help with this. I'm looking for either tabular data or a graph showing MAF airflow vs. voltage for the stock 997.1 meters. If anyone knows of one please let me know I would appreciate it.

 

Well since I couldn't find it I just made my own. Used Durametric to take the data required to build one. Now I know the limits of the meters for sure

 

Haha, that is what I figured you would have to do. Never seen that data floating around anywhere before. Care to share your findings?

 

I will trade data for data LOL.

You have some room left. Upgraded vtgs at 22-23psi is close, WGTs at higher boost forget it, would need larger MAF bodies or MAF-less.

 

M3 you are a bad influence haha! Watch those rods. Will have you analyze the comparison after we are set and try MAFless so we can all geek out!

 

Excellent point, there will be plenty of other limits like the rods. I'm merely only referring to the MAFs themselves . Hopefully nobody thinks "MAFs have some room" is an invitation to a free for all .

Honestly in the case of my setup I should be saturating the map sensor slightly before saturating the MAFs and about 80ish% inj duty on E70 @7krpm. So I think I will be done there. The hp/$ gain will go exponential after this .

Yeah I would find it interesting to try the 2 different calibrations back to back.

 

when do you see the MAFs max out ? I thought each one was good for 400-450hp worth of airflow.

 

It depends on a few things like your fuel, the way you phrased it assumes a bsfc. So lets speak purely in mass flow. I don't have the all the data yet to make the call of the "ultimate" limit. I know where I am comfortable, and that's at ~37lbs/min each. From 37lbs to 42lbs zone its fairly steep, I just don't have the data yet to know for sure.

If you have data with GT30s running MAFs in the area of 25+psi I would gladly look at it Most of my data collected from different 997s last year stop around 22-23psi with various VTG upgrades.


I will also add there is a expected variation in airflow measurement accuracy of 3% from part to part.