5 windows on the 3b dizzy blender??

[powercar]

have seen on different forums that people that use stand alone engine managment on the 3b engine have to modify the blender for the hall sensor in their dizzy for 5 windows instead of just one that's original.

the thing i'm wondering of is, how do they do this? what do they do to make the windows in the same accurate size?

[S2central.net]

I don't see why that would be necessary... Maybe its needed on one family of aftermarket ECUs - I could be wrong here - but remember the prime purpose of the hall effect sender is just to tell the ECU what phase the engine is on... The crank reference pulse appears every crank rotation... when that pulse appears within the one hall window then the ECU knows the engine is approaching TDC on the compression stroke of cyl #1... Having five windows would just be nutty...

[powercar]

the people i have seen doing it are running the autronic sm4 system

[twoqu]

Some 10V versions use a 5 slot chopper. Think its the later 2.3. Guess it might be possible to modify one of those or make a hybrid with 10V/20V distributor.

[powercar]

oki.
but one thing i where thinking of, why do they modify their dizzy actually? is it to get a more acurate spark to each sylinder?

[urquattro-island]

i think

they only do this, when they use the dizzy for signal for both injection and sparks. At least thats what i have been able to find out.

[urquattro-island]

for

example the 034m IIb uses the 5window dizzy on the urquattro for the injectors and spark. Once you wish to go single coil you must upgrade to IIc, to get the crank sender.

[S2central.net]

Seems an odd way to do things... One out of those five slots determines cyl #1... but we only needed one slot for that. Why not just count flywheel teeth from the reference position to ascertain injection & spark timing. Bit bizarre but there you go - must be a reason behind this method. I still don't see what advantage is provided by the five gap wheel.