Adjustable MAS???
Thread Starter
Instructor
Joined: Aug 2003
Posts: 172
Likes: 0
Adjustable MAS???
My mass air sensor needs replacement and I see that Granatelli now offers an ADJUSTABLE unit for the '85 and later.
Is this feature (adjustability) an advantage? How does this co-ordinate with the cars existing fuel injection system/computer controls??
Or is this a "gimmick" ?
Last, is the O.E.M. mass air sensor a restriction in a 400 cube engine? :confused:
Is this feature (adjustability) an advantage? How does this co-ordinate with the cars existing fuel injection system/computer controls??
Or is this a "gimmick" ?
Last, is the O.E.M. mass air sensor a restriction in a 400 cube engine? :confused:
Team Owner
Joined: Sep 2001
Posts: 62,067
Likes: 1,723
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
Re: Adjustable MAS??? (bigjack)
Its another 'sucker' mod in the magazines i bet.
Nobody has tried it yet, its new. But I'd advise against it.
When you get that big, the MAF can be a restriction, depending on the power levels youre at.
Nobody has tried it yet, its new. But I'd advise against it.
When you get that big, the MAF can be a restriction, depending on the power levels youre at.
Drifting
Joined: Nov 2001
Posts: 1,783
Likes: 2
From: Latham NY
Re: Adjustable MAS??? (bigjack)
It looks like the Microtech unit I have. The advantage is being able to adjust the airflow reading so the stock MAF table can be used. You will still have the 255gm/sec limit no matter how big a MAF you use.
Drifting
Joined: Dec 2002
Posts: 1,861
Likes: 4
From: Houston TX
Re: Adjustable MAS??? (Bluevette85)
It looks like the Microtech unit I have. The advantage is being able to adjust the airflow reading so the stock MAF table can be used. You will still have the 255gm/sec limit no matter how big a MAF you use.
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Re: Adjustable MAS??? (CorvetteZ51Racer)
:iagree:
If you have hit that "255 wall" that MAF could be adjusted (??) to give a lower reading. Then you might need to trim out the tables in the EPROM.
So, I see it as a "real" entity but to be used only when needed, with no real advantage on a nearly stock L98.
If you have hit that "255 wall" that MAF could be adjusted (??) to give a lower reading. Then you might need to trim out the tables in the EPROM.
So, I see it as a "real" entity but to be used only when needed, with no real advantage on a nearly stock L98.
Thread Starter
Instructor
Joined: Aug 2003
Posts: 172
Likes: 0
Re: Adjustable MAS??? (65Z01)
I'm not real understanding of computers and the system at work in our cars. So, in "plain words" what are your thoughts? I note that this is going in front of a 400 c.i. engine . I've got one of Ski's chips and need to replace the M.A.S. regardless. I don't understand how this unit can trulyoffer adjustability if the computer inputs try to "over-ride" the MAS.
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Re: Adjustable MAS??? (bigjack)
The ECM only "overrides" that data at part throttle while in closed loop mode.
At WOT the ECM ignores the O2 sensor data and uses MAF, TPS, and other inputs to calculate fuel flow (injector pulse width).
For your motor you might get some benefit from that MAF. The idea is to trim back the MAF output to keep the air flow data to hit the ceiling value of 255 counts.
At WOT the ECM ignores the O2 sensor data and uses MAF, TPS, and other inputs to calculate fuel flow (injector pulse width).
For your motor you might get some benefit from that MAF. The idea is to trim back the MAF output to keep the air flow data to hit the ceiling value of 255 counts.
