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-   -   Direct fire l & T with a cas and no ems (https://www.nopistons.com/performance-mods-20/direct-fire-l-t-cas-no-ems-63061/)

Mazdoo 12-06-2006 12:13 AM

What I did was I took a second gen crank angle sensor and modified the stock signal wheels. In stock form the bottom wheel has 24 teeth and the top has 2. I removed all the teeth on the bottom wheel except for two opposing teeth and on the top wheel I left it stock. You will have to remove the gears (wheels) with a press to re-align them. When reassembling stagger the top and bottom wheel so looking down you have a tooth every 90 degrees. you now have a dedicated timing wheel for each housing with no split for leading or trailing. what you end up with is just like the direct fire dizzy setups but because each wheel fires its own housing you don't get a wast spark bla bla bla.... anyway just a quick and not very well put together explanation.

just seems this way you could run 4 ignitors and 4 coils one for each plug.

or 2 ignitors and 4 coils

Either way you get rid of that big arse dizzy!!!!!

ArmyOfOne 12-06-2006 07:25 AM

I know trhis is a lame request but... Do you have any pictures? I am also curious as to how well it works without the falling edge.

Mazdoo 12-06-2006 09:46 AM

If you left 4 teeth on the bottom wheel at every 90 and ran just the bottom wheel you could run both leading plugs with a wast spark and furthermore if you wanted an offset for the trailing you could direct fir each trailing individually by installing the 2 tooth wheel back on top and offset the trailing (top) wheel whatever degree split from the correlating bottom tooth. this system works and the cas will fire j109 ignitors.

heretic 12-06-2006 07:54 PM

What is the benefit, exactly?

rmriggin 12-09-2006 01:41 PM

I don't know if they have been proven but direct fire mod users have said they notice smoother acceleration, a slightly different exhaust tone, easier start up, and some have reported noticeable improvements in gas mileage.

I would like to see either of the methods mentioned above. Pics are always a bonus. Having a direct fire system using a cas would be great because timing would be more accurate than with a dizzy.

Judge Ito 12-11-2006 06:06 AM

the crang angle sensor has 2 pick up coils, one for tailing 1 and leading 1. what pick up coils are going to send the timing signal to trailing 2 and leading 2???? I have seen this done in the past, but I never took a chance. on an electronic distributor, there's a rotor and distribution cap, distributing the timing between trailing one and trailing two, while it just uses 1 pick up coil for trailing and a seperate pick up coil for leading.



the way I look at it, you would need 4 pick up coils inside a crank angle sensor to fire trailing 1, leading 1.. trailing 2 leading 2.. one pick up coil per spark plug. ..Please explaine how you would use,just 2 pick up coils to fire 4 coils? when the timing signal comes from your pick up coils. Like I said i have seen it done before and would like some clarity.

Mazdoo 12-11-2006 09:27 PM

Some people want a mechanical advance so what I came up with is this.

Cas dizzy mix

[attachment=40402:attachment]

Trailing wasted spark will not happen with this, Basically you have 4 pickups and a 2 tooth wheel if you think of the pickups in clock positions you get 1 pickup at 12, 3, 6 and 9. Each pickup wired into a j109 then to coil. using 12 o'clock pickup as leading front and 6 for trailing front, 9 for leading rear and 3 for trailing rear. the two tooth wheel has opposing teeth allowing it to fire only 2 sensors at a time one directly across from the next. The 12 o'clock and 9 o'clock are mounted to the leading adjustable timing plate and the 6 and 3 o'clock to the trailing. When spaced at an equal 45 degrees from each other you get leading and training firing at the same time with no split with their own dedicated coils. the leading pickups and trailing pickups are mounter on plates that move to the left and right or each other for vacuum advance purposes that are no longer an option. Utilizing these plates you can advance - retard the trailing pickups allowing you to experiment with leading timing split. I'm going to hook up 2 j109s to each pick up and run 12 o'clock firing leading and trailing front at the same time then run 6 o'clocks signals to the same coils at a 10 degree split and the same with 9 and 3 o'clock in the rear just to see if it will work. Any thoughts?

Judge Ito 12-12-2006 07:46 AM

how would you run a crank angle sensor on 4 coils? I know of a way but it runs no split on leading and trailing. I'm looking to run a split between lead and trail without using a computer..

Mazdoo 12-12-2006 11:37 AM

You can do that, It would have a waste spark for leading but I'll post a pic of what you need to do.

Mazdoo 12-12-2006 02:45 PM

Locked timing cas, direct fire leading + wasted spark direct fire trailing independently. 4 tooth bottom wheel 2 toothed top. Adjust the split by offsetting the top gear to trail the lower gear by x degrees.

[attachment=40406:attachment][attachment=40407:attachment]


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