3.2 timing question

[avt007]

I'm troubleshooting a rough sounding 3.2 (my 86) and decided to throw a timing light on it. Yes, I know the DME controls timing, but here's what I don't get. The Bentley manual say the timing at 800 rpm should be 3.5 degrees BTDC. But on mine, it is 0 to 0.5 ATDC. It does advance with increasing rpm. Also, the fuel quality switch is supposed to affect timing as well, with some positions retarding the timing 2.77 degrees. Yet this switch has no effect on idle timing. Anyone know why?
thanks guys,

Rob

[DonMo]

Do you have a chip?

If not, Unless your ECU is starting to go bad, I don't know why it is off unles a temp sensor is advancing it for some reason.

[avt007]

No, it's a stock chip. But now I'm confused, because the factory manual says the timing is 3, plus or minus 3 degrees afterr TDC. And Bentley says 3.5 BTDC. Most strange!

[Fast951]

Originally posted by avt007
No, it's a stock chip. But now I'm confused, because the factory manual says the timing is 3, plus or minus 3 degrees afterr TDC. And Bentley says 3.5 BTDC. Most strange!

Your timing is correct.
IDLE: 680rpm: 0deg
760-1440rpm: -2.76 deg
1640rpm: +1.4deg.

[avt007]

951, what is your source for those numbers? Anyone else herew tried a timing light on a 3.2?

[Fast951]

Originally posted by avt007
951, what is your source for those numbers? Anyone else herew tried a timing light on a 3.2?

My source is the chip itself.
My business is tuning Motronic. We even rewrote the code!

Edit: The values I listed above will vary a bit depending on the different variable. The numbers I listed are the base IGN #s and should be close enough to what you should see.

[CruiseControl]

Fast951, where does it start advancing, and relationship to engine load AFM. Some numbers progressing up the rpm range would be of interest.