Dune Buggy Timing (Pulley) Question

The block in my buggy is from a 70 T2 and I've just replaced the 009 with the diz that came with the engine. I've determined that it is the correct unit for this engine and timing should be set at 0 degrees. When I adjusted the valves I made sure that the rotor was coming around to #1, and turned the pulley so that the notch lined up with the crack in the case. From here using the pencil-in-the-spark-plug-hole method I found actual top of the piston stroke to be about an inch to the right of the notch. I made a mark here and used it and a mark I made 180 degrees from it to do my valve adjusting.

Now I adjusted the points and statically set the timing to the mark I had made, an inch or so right of the pulley notch. Acceleration was poor, it was popping at idle, etc. I set up the carb using info here:

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were a little better but not much. After reading something somewhere I decided to set the timing by advancing it until I got my highest idle, then backing it off a bit. Suddenly the car ran better! So here's the question: Timed like this I'm almost 3 inches away from the mark I made for TDC and 4 inches from the pulley notch. The car does accelerate well but it's still not super smooth at idle. Is this likely to be the right spot? Is it possible that my pulley is 'on wrong?'

Reply to
Will Sheppard
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Sounds like you did everything right.

I wonder if the vac advance unit is working properly. If I'm not mistaken, that distrib is all vac, no centrif advance.

Suck on the vac hose and watch the advance plate; it should move to the stop and stay there.

Also possible that you're not getting enough vac from the carb port. You really need a strobe timing light at this point to verify advance.

Speedy Jim

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Reply to
Speedy Jim

Thanks for your reply. The plate moves when sucked and seems to be working well. When I had the 009 in there the timing worked out best at roughly the same 'spot on the dial.' I have been using the strobe timing light and when revved the pulley marks do move a lot...

What now?

Reply to
Will Sheppard

Is there any small chance that you set the static timing when the points CLOSE rather than when they open??

If your pencil test was anywhere near correct (I have no reason to doubt it), then initial timing 3" ahead of TDC doesn not add up.

Speedy Jim

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Reply to
Speedy Jim

I'm pretty sure I set the static timing right, I drive an old notch daily and am accustomed to how the light reacts...

However now that you mention it when I was setting the static timing something weird was happening. I start by making sure the rotor is heading up to the #1 plug wire then I set up my light then turn the engine clockwise until the light comes on. On my T3 (6V using a 12v test lamp) the light is out until I hit the spot and it lights up. On the buggy the light was on dimly as soon as I hooked it up. It flashed on nice and bright when I hit 'the spot.' It seemed strange to me but I figured it was probably different than usual because I'm normally using the 12V lamp to test a 6V system. What do you suppose this means?

Reply to
Will Sheppard

Dim light would mean the points aren't closing "tightly" (poor contact). Or something else is going on. Worth going over with a fine-tooth. Something smelleth.

Speedy Jim

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Reply to
Speedy Jim

I just checked the timing statically and the light is now behaving normally. The dim light condition seems to have been corrected by getting rid of the 009. Just when I thought we were onto something.... I also double checked my 'measurements.' My TDC mark is about 1" from the pulley notch and where I'm timed to now is actually about 2.5" to the right of it (3.5" from the pulley notch.) I took the buggy to the store tonight and it ran pretty well. I think it should accelerate a bit faster than it is but it is keeping up with traffic no problem.

I guess I should do the pencil-in-the-sp-hole check again to double check my TDC mark. Anything else I can do or should consider?

Reply to
Will Sheppard

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