timing control with a stock points distributor???

[Army of Six]

i was driving around today and thinking....why cant you install a petronix ignitor to replace the points, lock down the vaccum and mechanical advance weights and use the pertronix to trigger the ECU and then the ECU can handle the timing control through the coil???

 

[wallaka]

No reason why not.

 

[fordconvert]

It just depends on what sort of a signal the ECU is looking for. From what I have seen what you could get from points is not going to do it. The pertronix wont help, I think it would be worse because its doing its own processing of the trigger. Even with Megasquirt you cant do timing control with points. You can use them as a tach reference but not for timing / coil control. You could use a points dizzy if you had a crank trigger.

 

[Army of Six]

the points will be gone and replaced with the pertronix ignitor II similar to this ( http://www.summitracing.com/parts/PNX-ML-181/?rtype=10 ) which to my knowledge is nothing more than a hall effect magnetic trigger.

 

[wallaka]

http://www.302w.com/Windsor_MegaSquirt_Part6.aspx

 

[Army of Six]

http://www.302w.com/Windsor_MegaSquirt_Part6.aspx

YYYEEEEEEEEEESSSSSSSSSSSSSS...thank you thank you thank you!

Vic

 

[fordconvert]

Interesting. The megga manual used to say you cant do that. Guess thats the beauty of Megasquirt, someone wrote software to make that work. The guy makes no mention of 'indexing' the distributor to make sure its firing when the terminal is aligned with the rotor. In theory it should be close but there are a lot of ways you could get it off. The systems I have done we were not trying to keep it working stand alone so all we had to do is rotate the dizzy to get it close and then change the offset to get the timing back. We just cut a hole in an old cap and used a timing light to see where it was firing. The first time I ran into this the guy was having a dead spot. Guy worked at it for several months before we found the problem. At times the rotor was too far from the terminal when it fired. First problem was the higher voltage would induce noise in the system and screw up sensor signals. After we worked around that problem we found the cap was destroyed and all carboned up with only a few hundred miles. Got it set so that when it fires in the middle of the timing range its centered on the terminal and as far as I know its running great. With a small diameter V8 cap you could really get into trouble. The ones I have worked on were HEI's. At least with a 6 even the small caps have a good distance between terminals.

 

[Army of Six]

i was wondering about the distributor "phasing".

well, im going to give it a go. i did run into one problem. i went to radioshack today to get the 1K ohm resistors but it doesnt mention what wattage it should be. what do you guys think is the correct wattage for the resistor. they had 1/8th 1/4th 1/2 and 1 watt resistors available

any ideas?

thanks again for the help,
Vic

 

[fordconvert]

I would go with 1/2 watt. I know I am running one size too small and it runs warm but has been working for 2 years. I just dont remember if I used 1/8 or 1/4.

 

[Army of Six]

1/2 watt it is then. also, where is the ideal place to install the pull up resistor. i know it would be a nice and clean setup to just jump across right at the pertronix but im thinking that i will pick up alot of noise under the distributor cap. would the resistor be better off being placed near the ECU just before the tach input pin???

 

[fordconvert]

Mine was on an HEI module so the terminals were side by side already. I dont think it would make any difference where it was. It should be fine closer to the ecu. If you think about it in the normal circuit that load would be the coil anyway which was not connected close to the module so as far as it knows all will be normal.

 

[Army of Six]

im just concerned because i had alot of interference with my tach signal and still do somewhat. i had to run a zener diode in line to clean up the tach signal. but if you are not having any trouble picking up excess noise under the distributor cap then i will give that a go.

thanks again,
Vic

 

[fordconvert]

On mine I am running parallel modules. One runs the coil the other with the resistor runs the ecu. With the single module I would always have random spikes on the tach line. Only change I made was adding the module and its been fine ever since. The reason I tried the second module first is I had a spare module and resistor laying around. Would have had to mail order the other possible fix parts.