![]() Sounds coming from the engine usually mean something is wrong, but it could just as easily mean that the timing is off. The life of your engine could be reduced, depending on several factors. That sudden succession of shudders, shakes, and quakes don’t exactly inspire the best of confidence in your vehicle’s engine. So I think the light should be set to 29* in order for the two stock TDC marks to line at 3400rpm(really getting 35* total).Īttached is a diagram(not sure who the original illustrator was, but thanks) I used to set my 3* mark on the pulley.Extend the life of your engine with this timing light from Dirautos. ![]() If you think about it, after it's timed as noted in my first paragraph, the light strobe needs to be slowed a bit more order for the factory TDC marks to line up. My guess is that the timing light would need to be set to 29*. Now, once timed as noted above, I was going to wait until the weekend to test/confirm(No offence, Glenn- I just always like to test for myself) whether I needed to then set the timing LIGHT to 35*(32+3) or 29* (32-3) in order for the two factory TDC marks(case and crank) to line up at 3400rpm. To be honest, I thought I finally understood Glenn's approach yesterday, but I think I'm back to my original position: To get 35*, use the 3* BTDC crank pulley mark(if you have one) and time it at 32* at 3400rpm using that mark & the mark on the case. Simple, right? (after 5 decades with these excellently engineered machines) Like Glen, I usually see about 32*, after wear in, on the factory units, and they are most accurate at over 3200 RPM, the point, above which there will usually be no more timing observed, with higher RPM. 912), or 031 (ROW, & over the counter replacements), at a full dynamic timing of 32*, at about 3300 RPM, where the total ignition timing, is "all in". Most motorcycle, or dedicated air cooled (+ fuel, + oil cooled) engine devotees, realize that these static compression ratios (C/R), are roughly the equivalent of around a point higher, thus, a realistic, over 10:1 C/R engine, which we are now trying to tune to a poorer octane fuel.Īfter all these years, I now set my BR18 (later 356), 022 (-'67 912), 061 (US del. The currently available PC 10% ethanol, contains less energy, than "real" gasoline, and we can no longer safely, run that much timing, with the stock, factory nominal 9.3:1 static compression ratio. runs from the camshaft gear, at 1/2 of crankshaft speed, needs to be doubled, for a direct comparison. Glen's graph, is directly from the original factory maintenance manual, and is shown in only the distributor RPM, and as the dist. The advent of the "PC" 10% ethanol, and changes in how each country now rates the octane of currently available "fuels", has changed, and must be accommodated for. Also, one needs to realize, that these figures were from a time when there was much better "tetraethyl leaded 100+ octane "real" gasoline, was commonly available. of 3*, is at the pulley, and came from the original static timing, before the engine start. His council, to add the factory book spec. He shows the distributor speed and degrees of timing, "in the distributor", on one side, and engine speed and degrees of timing, "in the distributor", on the opposite side of the chart. ![]() That first curve, in your post, looks like one of Bruce Smith's, and demonstrates one of the nuances of the interpretation, of the curves. ![]() in that kind of scenario it will get you home.Ĭlick to expand.Joel, these timing curve graphs, are not the easiest to read, when one first starts to learn the "science" of ignition timing. you wont have optimum performance, but it will be drivable, say if you had to remove the dizzy to swap points out on the side of the road and needed to re-time it and didnt have a full proper timing light, only a test light. If your car is already running and can start, then who cares about doing it statically, just do the dynamic timing at speed (full advance/3000+ rpm).Īside from doing static timing when first putting a distributor in, static timing can be used in emergency situations if you have a timing issue and need to get the car back home or from point a to point b. Once you have the car started and running, then you need to dynamically time it at speed/full advance (aka 3000+ RPM) to get the timing right and dialed in. if you take the distributor out and put it back in and dont know where you are at, you can static time it with a test light, in order to get it 'driveable' or running (wont run best, but it will run). IMHO, static timing should only be used to get the car running. ![]()
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