vindaloo

Aimless question really but why is the MAF situated before the turbo?

To accurately measure the airflow entering the plenum, surely, it should be after the turbo or after the i/c.

The question came to me whilst wondering about inlet pipes and the efficiency (or lack of) of the standard inlet trunking, MAF and turbo inlet pipe. Maybe they can't be made robust.....

Vindaloo.

StickyMicky

because if it was after the turbo it would melt?

vindaloo

A reasonable distance away from the turbo on the induction side? Pre or post i/c is what I meant. Would it still melt d'you think?

It has occurred to me that MAFs can be fragile. Maybe it wouldn't like the extra heat or vibration...so maybe that's why it is where it is...

Jeremy.

greasemonkey

Because it's a mass-airflow sensor. The only way to get accurate readings with this sort of system is to measure the air at normal atmospheric pressure.

[quote] To accurately measure the airflow entering the plenum, surely, it should be after the turbo or after the i/c. [/quote
No. It would be much more difficult to accurately measure the volume of air after it has been compressed.

Robustness isn't the issue. Accuracy of measurement is. MAF based systems will always meter the air at normal atmospheric pressure. It's MAP (manifold absolute pressure) based ECU's that calculate air volume on the basis of sensors placed in the pressurised side of the induction tract.

john banks

Have a look at blow through MAF systems.

Andy.F

Not the case ! As it is a mass flow sensor it measures the MASS FLOW not volume. If it did not automatically compensate for air density then you would get a wide variation in mixture depending upon atmospheric pressure.

Andy