NefMoto

Vehicles => Vehicle Tech => Topic started by: zillarob on October 20, 2012, 11:07:57 PM



Title: Maf flow straightener
Post by: zillarob on October 20, 2012, 11:07:57 PM
What is the general consensus on these things? Seems like a good idea to me and I would think there is a reason ze germans do it.

The maf is the hitachi 85mm mustang/lightning one dude was blowing out for 45 on fleabay a while back. The straightener and screen were surgically removed from an 85mm bosch maf out of some bimmer.

So, before I chuck it up on the lathe, run both like ze germans, or just the screen ala hitachi? Im kinda leaning toward just the straightener.

(https://lh6.googleusercontent.com/-pT4Jm9RjIro/UII6SjQxm9I/AAAAAAAAAx4/qElW5fPrUqg/s512/IMG_0699.JPG)


Title: Re: Maf flow straightener
Post by: diagnosticator on November 03, 2012, 07:34:37 AM
Without the flow straightening screens, as fitted to the sensor OEM, the accuracy of the sensor over the required flow range of the sensor calibration is no longer within the calibration/accuracy specified for the sensor performance. There is no way to know how the calibration is effected, except that it is no longer accurate according to the flow calibraton. Turbulant flow conditions, are by nature chaotic, therefore, the sensor output becomes chaotic when the laminar air flow screens are removed.


Title: Re: Maf flow straightener
Post by: nyet on November 03, 2012, 04:41:35 PM
No clue :)

what i would LOVE to see is if somebody took one of our intake systems to a maf calibrator (airbox and all) and ran some tests (with and w/o screen, cone filter, etc).


Title: Re: Maf flow straightener
Post by: zillarob on November 03, 2012, 11:24:48 PM
Without the flow straightening screens, as fitted to the sensor OEM, the accuracy of the sensor over the required flow range of the sensor calibration is no longer within the calibration/accuracy specified for the sensor performance. There is no way to know how the calibration is effected, except that it is no longer accurate according to the flow calibraton. Turbulant flow conditions, are by nature chaotic, therefore, the sensor output becomes chaotic when the laminar air flow screens are removed.

Thats kinda what I was thinking. I know people have run these for years without probs, just seems to me it might smooth things out a little when it comes time to tune.



No clue :)

what i would LOVE to see is if somebody took one of our intake systems to a maf calibrator (airbox and all) and ran some tests (with and w/o screen, cone filter, etc).

Agree. Maybe I can talk buddies at VAC Motorsports into showing me how the flowbench works. Have to read up on powering the maf though. Cant be as easy PC power supply and voltmeter?
Wouldnt be able to use the airbox though. This maf is 85mm straight through so tough to fit.


Title: Re: Maf flow straightener
Post by: phila_dot on November 04, 2012, 12:02:46 AM
VAC Motorsports?

Where are you located?


Title: Re: Maf flow straightener
Post by: zillarob on November 04, 2012, 12:26:26 AM
Bout an hr west of philly


Title: Re: Maf flow straightener
Post by: phila_dot on November 04, 2012, 12:37:58 AM
Bout an hr west of philly

Ahh ok.

They're right up the street from me.


Title: Re: Maf flow straightener
Post by: zillarob on November 04, 2012, 12:45:46 AM
Nice! I love going down there.
Great people and lots of cool shit going on in there. And the Bocce club around the corner makes a mean cutlet and greens sandwich, lol.


Title: Re: Maf flow straightener
Post by: ddillenger on November 04, 2012, 12:51:31 AM
Question: I know when used in fords, a metering tube is used. The color (corresponds to hole size) is changed in order to calibrate the maf for different injectors. Did you get the metering tube, and if so, will you be using it? I'd think not since you're not using the ford sensor, but I have no idea what the ramifications of not having it would be?


Title: Re: Maf flow straightener
Post by: zillarob on November 04, 2012, 12:57:50 AM
Question: I know when used in fords, a metering tube is used. The color (corresponds to hole size) is changed in order to calibrate the maf for different injectors. Did you get the metering tube, and if so, will you be using it? I'd think not since you're not using the ford sensor, but I have no idea what the ramifications of not having it would be?

I dont think any of that applies on our cars and dont have any of them. Just a straight 85mm housing with a hitachi maf.


Title: Re: Maf flow straightener
Post by: ddillenger on November 04, 2012, 12:12:46 PM
I didn't think so, figured it was more to get the stock sensor calibrated correctly, but couldn't hurt to ask!

Without a flow bench, isn't setting up a non-factory maf trial and error?


Title: Re: Maf flow straightener
Post by: zillarob on November 04, 2012, 03:02:25 PM
I dont really know a whole lot about this or if a bench will even flow the gram/sec that our motors can eat. So not sure close you could get to an actual calibration like this.

I am just curious if there are any nasty (turbulent) spots that the straightener would smooth out. Should be able to see some trends an decide from there.