747 Timing Connector and misc questions

[Jason Weir]

 I was under the assumption that disconnecting the timing connector
on the GM TBI, took the timing control away from the computer so you
could set the initial timing without the computer getting involved.  I
am trying to change the timing curve in the chip so to start with I
graphed the existing curve. I got two similar graphs with and without
the connector connected? I put the graph up on my webpage.  By the way I

have set the timing at 12 degrees initial advance at the distributor and

the distributor has no vacuum or centrifugal advance.

http://home.att.net/~jweir/graph.html

    Is the timing connector just for timing at idle and knock control..
What am I missing.. Second question is anyone using Needham's PB-10 prom

programmer? I am looking to buy one and that one seems to be what I need

not to mention it is rather cheap. Check it out and let me know what the

consensus is..

http://www.needhams.com/pb10.htm


--
Jason Weir - 88 YJ - 258 / Howell TBI  145K and counting
Fayetteville, North Carolina
JTW Web pages at http://home.att.net/~jweir
mailto:jweir at worldnet.att.net