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Mallory Dual Point gap

BJ8TONY

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Hello all

I am using a Mallory dual point distributor on my BJ8 and would like to know what others using the same distributor
are setting their point gap at. I am thinking .028 each.


Thanks.

Tony
 
I'm thinking I used .025" (.026"?) but it's been so long since I've set them**, I don't remember! By nature of the dual-points, you already have a longer dwell time, so you needn't add more by opening the gap wider.





** currently, I'm only using one (1) set of points as a trigger for an MSD 6AL ignition system, so there's virtually no arcing at the points__set & forget!
 
Tony, Mine is a Mallory dual point series 23 and the info I have says to set them at .028 which should give 35 +/- 2 degrees total dwell. That is what I set mine to and it worked well for me for several years until I got lazy and installed a Pertronics in it.
Dave
 
Thanks for you reply's
I did set them up at .028 and it seems to be running fairly well.
Now it is on to a carb problem.
I am running triple Webbers 45 DCOE's.
On 1 carb I get little to no change when I try adjusting the idle mixture screws.
Always some challenge!!

Thanks again
 
After the valves, ignition (points and timing) are set, loosen the linkages and balance the carbs; individual barrels of each carb first, and then the three carbs together. When they're balanced and you're retightening the linkage, take into account the slack in the individual linkage ends, so that each carb reacts at EXACTLY the same time. If one (>1) carb comes in before another, you'll never achieve crisp response.

Once the airflow is equal, then you can start working on mixture strength__but take heart, there are only sixty-eight (68) variables :glee:

ct3.jpg


ct2.jpg


air_bypass_adjustment2a1.jpg


air_bypass_text.jpg


Once you start getting close on idle/low speed settings, you can cheat a little bit by pointing an IR thermometer at the individual exhaust header tubes (as close to the head-port as possible, as long as you can read ALL SIX at the same point). By increasing/reducing mixture volume, you can walk the EGTs pretty close together.

Unless you've got a chassis dyno at your disposal, I see lots of test drives, and numerous First Class plug-cuts in your future.

Once you get the carbs set, leave them alone! With the exception of a slight increase in mixture strength after moving to Florida, the 45 DCOEs on my car haven't been touched since not long after those first couple of pictures were taken. Incidentally, When I first purchased them (1986) I specified 36mm main venturis, for improved signal strength (aka, higher velocity through auxiliary venturi than with the more common 38mm chokes).

Good luck
 
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