How To Tell If Maf Is Blow-through Or Draw-through?

sen2two

I've been lubing and pulling it all morning
Jul 18, 2013
396
58
49
Just bought a used MAF locally. It's an 80mm C&L. It was being used on a Procharged car. In the pics of it he sent me before I purchased it, it was set up as Blow-through. But when I was talking to him, he said he used it as a draw through as well. Both ways he had no issues.

I wasn't aware this was possible...

What is the actual difference in a MAF that is designed for Blow-through or Draw-through? If any...
 
  • Sponsors (?)


Just bought a used MAF locally. It's an 80mm C&L. It was being used on a Procharged car. In the pics of it he sent me before I purchased it, it was set up as Blow-through. But when I was talking to him, he said he used it as a draw through as well. Both ways he had no issues.

I wasn't aware this was possible...

What is the actual difference in a MAF that is designed for Blow-through or Draw-through? If any...


Oh Nooooooooooooooooo. Does it have replaceable sample tubes?
 
That dosn't answer the question.

I'm asking what is the difference between a Blow-through and a Draw-through MAF. How does one meter air differently from the other?

And to respond to the "sell it" part. I have used 2 other C&L MAFs. Both had zero issues. This MAF, came off a very quick Procharged car. Street driven as well.
 
If the element itself is OEM then the meter should be draw through. If element is after-market, then it's anyone's guess.

Hopefully, you can identify your housing: Not what you're looking for but should tell you what it was intended for at least. To my knowledge, these housings are all draw-through. Making them blow through generally requires a change of electronics and new set of data points for the new transfer function (most tuners will create their own so long as the meter is consistent).

http://www.cnlperformance.com/Calibration-chart.php

Do you have pics or part numbers?

Since mass air meters operate by varying resistance, you can pretty much use any meter as a blow-through meter so long as it's not pegged. This is where the previously mentioned aftermarket elements come in. They can be used with a relatively large sample size and not peg as the result of additional heat. This causes some resolution loss but electronics are a lot better than they used to be.

OEM electronics were not intentionally designed to be blow-through.

Hope that helps.
 
  • Like
Reactions: 1 user