MAP map or MAF map

Zublin, Bryan (SD-MS) BZUBLIN at
Sat May 6 01:12:40 GMT 1995

I believe that a MAF based system would be easier to calibrate compared to a 
speed density design (I have never confirmed this).  If you have the 
calibration curve of the MAF meter (volts output vs. kg/hr mass flow) and 
the flow rate of the injectors (cc/min), then it should be a relatively 
simply process to determine the injector pulse width based on the air-fuel 
ratio that you want.  I would be willing to bet that this first order 
approximation will be good enough to get the engine to run fairly well.  Of 
course, second order enrichment factors will have to be applied for startup, 
idle, acceleration, etc.

I have measured the steady state average flow rate of the injectors that I 
have.  This is fairly easy.  Does anyone on the list have calibration curves 
for the MAF meters used on the Ford vehicles (specifically the one used on 
the 5.0 L Mustang, made by Hitachi)?

Bryan Zublin
General Instrument, San Diego, CA, USA
bzublin at
From: owner-diy_efi
Subject: Re: MAP map or MAF map
Date: Monday, May 01, 1995 8:35AM

Is a MAF based system going to be easier to calibrate than a speed-
density system?

Also, what sort of aftermarket engine management systems are there for old
V8s (I won a 1965 Buick Skylark Gran Sport) ?  I would really like to get
a system that has knock and oxygen sensor feedback, spark control and
throttle body injection.

Charles Mott

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