Date: Sun, 8 Feb 2009 15:39:38 -0800
Reply-To: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Subject: Re: A New Perspective on Vanagon Syndrome
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=original
OR............start with an ECU and fuel system that already uses an Air
Mass Meter.
my 88 740 volvo is such .
It's ordinary electronic port fuel injection.........just like a vanagon
.....
has the normal inputs..........coolant temp, throttle switch ( though it is
a bit more evolved TPS than what a vanagon uses ) ..........
but seems to me that it wouldn't be impossible to operate a vanagon engine
with a ECU and harness and Air Mass Meter from a similar size and # of
cylinders engine.
Throttle switch is the only thing that comes to mind right now that's very
different.
the rest is the same just about .............my volvo uses a distributor,
the Igniter is in the ECU ......etc. Just like a 2.1 waterboxer.
Seems doable to me !
If I see a wiring harness on a 740 Volvo in a pick-n-pull., plus a non-turbo
ECU ...............hmmm.
I already have a spare engine wiring harness.......
and a couple of spare air mass meters......
heck.........it's almost done !
scott
www.turbovans.com
----- Original Message -----
From: "John Bange" <jbange@GMAIL.COM>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Sunday, February 08, 2009 10:28 AM
Subject: Re: A New Perspective on Vanagon Syndrome
> On Sat, Feb 7, 2009 at 4:07 PM, pdooley <psdooley@verizon.net> wrote:
>> Probably discussed before, but the *real* fix is to replace the AFM with
>> a
>> MAF.
>> Figure out the output signal profile of the AFM and build an interpolator
>> to
>> plug into the MAF.
>
> One of the guys at Bostig mentioned investigating such a device once.
> Trouble is, "hot wire" air flow measurement basically combines intake
> air velocity, temperature, and pressure and reports them as a single
> value to the ECU. This is fine if the ECU is designed to use that
> value, but it gets messy when you try to apply it to an ECU like the
> Digifant, which reads air temp and (velocity/pressure) as two separate
> values. It would require a pretty gnarly lookup table to "unbake the
> cake" and get the two values out of the single hot wire value, and the
> only real way to build that table is with hours of work at a flow
> bench rigged to feed air at a wide range of temperatures, followed by
> probably twice as many hours tweaking the system on the engine to get
> it refined. In the end, it'd have to be something some nutter does out
> of sheer personally folly, rather than a kit someone designs with the
> intent of making money. I once sketched out a plan for doing it, but I
> can't even find the time to fix the bad oil cooler O-ring on my '90 GL
> that's been sitting for 5 months, so that plan resides in a folder on
> my computer, right next to the Atmel microcontroller pseudocode I
> wrote up to digitally mimic the analog Idle Control Module....
>
> --
> John Bange
> '90 Vanagon - "Lastwagen"
> '90 Vanagon GL - "Wiesel"
| 
