RE: AFM->MAF sensor conversion

["MSI: John Christensen" <JohnC@xxxxxxxxxxxxxxxxx>]

Obadiah Fayth wrote:

>I stumbled across a web site for a company that makes a device that allows
a mass air flow sensor (MAF) to be installed in place of the air flow meter
(AFM) on Bosch L-Jet cars. Their site also states that you can use the
device to adjust the mixture from within the cockpit. Sounded
interesting... The company's name is "Splitsec" and they can be found at
http://www.splitsec.com/ Anyone used their products?

This product (called the ARC2) has been discussed quite a bit lately on the
Porsche List.  Huntley Racing in San Diego is reselling it in a package that
includes a mass airflow sensor (also available from Split Second) for the
944 turbo and so far reports have been favorable.  The ARC2 is touted as a
"signal interceptor" that allows you to remap the signal from the AFM or MAF
to the computer.  This means that you can optimize the injection system to
work with your particular car regardless of the mods you make to your
engine.  In other words, if you add hotter cams and need more fuel in the
midrange, you simply twist a knob.

You need to install an Air/Fuel ratio gauge to monitor the effect of the
adjustments, but a dyno is not required.  I have yet to hear from anyone who
has used this device on a normally aspirated car, but the performance gains
with the ARC2/MAF alone probably make it a pretty expensive proposition.
The ARC2 sells for $500 and the MAF with requisite plumbing will probably
set you back another $400-$500 or more, depending on the mods you have to do
to the intake system.  In a turbo, this setup allows you to turn up the
boost (which is cheap to do) and walk that fine line between reliability and
a blown head gasket.  

The Huntley kit adds 90HP to a 944 turbo compared with the 50HP gain I have
from my current aftermarket chips  (yep, plural -- the 944 turbo has two
different computers), so it is pretty cost effective and is why I am
considering buying it.  However, adding that kind of power to a normally
aspirated engine would obviously require a lot more work since you would
still need to increase flow to the engine via cams/headwork/etc.  That said,
it is a pretty interesting device and probably a must have for anyone
looking to extract that last bit of power from their pulsed injection car.  

- -John
Seattle, WA
'69 GTV
'86 944 turbo

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