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Re: More MB thinking

In message <c549e780.36010653@aol.com> QSHIPQ@aol.com writes:

> Though the MB doesn't have an o2 sensor, if it has a WOT switch, it really is
> the same as the MC in terms of the MAP.  Since the MC assigns a FV value to
> the lambda circuit, effectively you have a mechanical injection system (albeit
> with more fuel than mechanical alone).  Since the MC can handle some serious
> mods with no changes to the fuel system, my thinking is, so can the MB.
> Although Orin is probably right that you have a increase need for fuel with
> increases in VE, the usual effect of VE in terms of fuel would be seen more
> before WOT than after.  What you have to find, is what the MB computer does
> with the WOT signal.

The MAC12D seems to be a clone of the MAC11 with the single omission of
lambda control.

The WOT switch provides initial overboost, WGFV control and FFV valve
control.  The effects are best seen with jumpers attached to the WOT
input to the ECU - that way you can hold the throttle opening constant
and see just what the switch does.  Using Orin's digital duty cycle
display and a diode light on the wastegate frequency valve, it's
easy to see it affects both - it increases the duty cycle on the fuel
frequency valve, and it "switches on" wastegate frequency valve control.

 Phil Payne
 Phone: 0385 302803   Fax: 01536 723021
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