Advancing ignition timing....

[canada karl]

I'm about to change the points ,rotor condensor etc on my 76 530i(Thermal reactors removed) Seems to me I read on this forum something about advancing the timing "a pencil mark width"on the distributor to get a bit better performance. Can anyone elaborate on this?

[Karl in KS]

Setting static timing at the distributor will get you started, but timing should be set with the engine running--the flywheel timing mark at specified RPM. On my '81 the book says 2200rpm. Since advance increases with rpm, setting to the timing mark at lower rpm will give more initial advance. I set mine to the timing mark at 1700-1800rpm. We did a little test with a G-meter, and the extra advance really does give better acceleration.

[canada karl]

Thanks for the info Karl.

[Brian Smith]

Advancing the timing beyond the factory specification can lead to high rpm at idle, perhaps high enough to trigger the idle system's self-regulation system, leading to cold engine idle speed pulsation. If you can manage to get away with a couple of extra degrees without idle pulsation and without light throttle low rpm pinging, then you will be increasing economy and performance throughout the rev range.

If you have a nice dial-back digital timing light, you can experiment with altering your setting 2 degrees at a time until you experience something unsavory, then dialing it back a degree and retesting for the bad condition, perhaps backing it off an additional degree.

You might find, as I do, a differrent happy point during cool weather operation than you find during the heat of the summer.

If it were me, I would upgrade to full electronic control before fooling with the factory setting. Points wear and inaccuracy can, in 3000 miles, exceed the couple of degrees of extra advance that you might be able to get away with under ideal points adjustment and condition.

[Mike W.]

Seems like advancing the timing more than factory spec used to do more good than it does now. I attribute it to the change in gasoline, which only vaguely resembles what it used to, at least here in California. But it's a seat of the pants thing, time it, crank in a little more advance and see how it runs. If you like it better, leave it, if you're thinking it's not quite as good, turn it back. They built the US spec cars to pass smog, they built the euro ones to run good, and I bet they just set it where they ran best.

Now theory says, advancing the ignition more than factory spec, will get you more torque, but perhaps a bit less peak HP. Your call, but driving in the real world is what counts. And I too would reccommend a 528i distributor and ignition system, it's a "hotter" spark, much more reliable than points and condenser, and has a better advance curve. If you need to keep the original curve to pass visual smog, one from a 78-79 6/733 would have the electronic part with the the thermo advance curve.

[cpalmer]

I just installed a pretronix ignition system last week, and set the timing to original specs.

She seems much happier, especially after a new ground strap yesterday.

Of course, the up-grade to a 528i ignition like mike w said who be the way, but the pertronix was easy, fast, and 70 bucks. I'd already burned three set of points in 6 months.

I'm hoping I don't have to look at the distributor for a while.

[Mike W.]

I'd already burned three set of points in 6 months.

Reminds me of my Bavaria days. Seemed like it was questionable if I could get thru vacation without #&%ing with the points. Got the wife a 528i E12 and the only related problems were when I gassed up in Death Valley and got what was one step this side of diesel and had to adjust timing on the road.