Schrick Cam installation

[Alan Pritchard]

How does the ecu know where tdc is? Apart from the hall sensor it has no
other reference does it? The timing marks on the flywheel are 0, 12 16 and
18 iirc, there maybe others.... So I guess the hall is triggered 60 degrees,
but the actual spark at idle doesn't take place until the 12-18 btdc
marks..... javad has mentioned this as well that the base timing cannot be
changed, I just don't get how the ecu knows...

Best Regards,
Alan Pritchard

Network Administrator
Mechanical Design Engineer
Seaeye Marine Ltd.
+44 (0)1329 289000

 -----Original Message-----
From: 	Tony Lum [mailto:tlum at flash.net] 
Sent:	04 May 2004 16:03
To:	Alan Pritchard
Subject:	RE: Schrick Cam installation

At 02:41 PM 5/4/2004 +0100, you wrote:
>Mine just has a nut holding the dizzy in position. Rotating the dizzy
>definitely alters the timing in some way, I put the fuse in the fuel pump
>(actually I have a jumper switch wired in) and altered the timing like
that,
>although I don't know what happens when you un-jumper again. When set to 22
>btdc the car ran awful, so something definitely had changed, 16 and 18 felt
>the same, so I opted to leave it at 18.... I don't know how the ecu can
tell
>that the timing has been messed with, afaik the only sensor it has is the
>hall sensor on the dizzy, although saying that there is something on the
>bellhousing which im not quite sure what it is. I would be interested to
>find out mor though.
>
>Best Regards,
>Alan Pritchard
>
>Network Administrator
>Mechanical Design Engineer
>Seaeye Marine Ltd.
>+44 (0)1329 289000

Hi Alan,

Your engine should have the CIS-E III fuel management system, which means 
that the ignition advance is electronically controlled.  This can be 
confirmed by examining the distributor and noting that there is no vacuum 
advance diaphragm mounted.  The hall sensor triggers 60 deg in advance of 
TDC and the computer triggers the ignition according to maps programmed in 
its separate ignition ecu.  The ecu has 2 maps, one for premium and one for 
regular gas if the knock sensor detects pinging.  So I'm guessing that 
manually setting the distributor to anything but the OEM setting is just 
going to mess things up.

Regards,



-Tony

'80 5KS
83 urquattro #DA900302
'85 4kq
'87 5kcstq
'87.5 coupe GT (CIS-E III F.I.)