So i'm switching to the N/A dizzy...

**n2o_matt** · 8-22-09, 19:33

After screwing with my 2 VR sensors in the GT dizzy long enough, i've decided to try out the hall effect sensor in the N/A dizzy.

I bought the dizzy - $42 at a u-pull-it

Now i'm trying to get my board set up but i'm quite confused. I started by following cenatix's write up here: http://www.mx6.com/forums/1g-faq-ele...tallation.html (DIY Megasquirt Installation)

But after being a bit confused on why he was jumpering some stuff I went here: MSnS Extra Ignition Hardware Manual

What was he doing? Any suggestions on which way i should do it? Does the N/A dizzy have a Hi to low or a low to high Hall sensor? I would test it the way the manual says but I don't know of an easily accessable 5v source. It appears that is why cenatix pulled 5v off the board for the dizzy - is that a good idea?

**Matt Cramer** · 8-25-09, 10:33

The NA distributor is actually a VR sensor, but he's using the ignition module itself as if it were a Hall effect sensor.

**n2o_matt** · 8-26-09, 20:39

what? really? I'm not saying you don't know what's going on, but did you read his post?

After looking closer at his post it appears to be setup exactly like a low to high hall effect sensor. The only weird part is that he deviates from the mega manual and has power on pin 24 and his signal on pin 25.

MSnS Extra Ignition Hardware Manual

**Zach** · 8-27-09, 11:23

Matt, why are you changing? I love the turbo setup. Nice and easy. Just grind off two teeth and take the rest of the innards out of the turbo disty

**Matt Cramer** · 8-27-09, 12:05

I did and had mostly been trying to shed some light on what was going on. His post is an odd early version of the low to high input mod from the VW crowd.

**Zach** · 8-27-09, 13:10

I wonder if switching to the earl's garage daughter card would be better suited?

**n2o_matt** · 8-27-09, 18:27

IDK - but i have the N/A disty locked and installed. It starts and runs, but yeah, its def not right. Right now the timing mark on my crank pully is about strait up (TDC) and I can't really get it to move with the trigger angle. It runs best a about 80 for what ever reason though.

I really don't get how it can use a 4-0 wheel any way. How does it know which cyl fires next? I don't really know how it even runs lol. I can't believe i didn't realize that.

Well, i've already got the n/a disty - guess i'll try to figure out what the heck he did. I wish he would have mentioned that it wasn't standard.

**Zach** · 8-27-09, 19:07

get a new crank pulley...I have one. paypal me $15 and it's yours priority

**n2o_matt** · 8-27-09, 20:15

Quote:

Originally Posted by Zach

get a new crank pulley...I have one. paypal me $15 and it's yours priority

I replaced it today.

I also just tried switching from the megamanual high-low method to following his exactly. The strange part is, i got the exact same results

IDK what to do next.

**Matt Cramer** · 8-28-09, 9:55

Quote:

Originally Posted by n2o_matt

I really don't get how it can use a 4-0 wheel any way. How does it know which cyl fires next? I don't really know how it even runs lol. I can't believe i didn't realize that.

The answer is that it doesn't... and with a distributor, it doesn't need to.

**n2o_matt** · 8-28-09, 12:08

good point, all it needs is a reference to TDC so it knows when to fire, and the dizzy takes care of delivery to the right place. Makes sense.

Do you know where I can find out more about this VW mod? I searched the MSx Extra forms and found it mentioned they do it differently, but I'm not exactly sure how or why.

From what i've gathered so far they power pin 24 to basically invert the signal. But when I switched to cenatix's method i'm having the same problem. I think i'm going to run over the board and make sure every thing is how he had it and then maybe try and experiment with some more trigger angles today...

**n2o_matt** · 8-29-09, 20:50

I emailed cenatix, and he was saying that he forgot to put in the writeup that the dizzy needed to be locked in the full advanced position. So I got another dizzy, and locked it at full advance. I have the same exact problem.

I experimented with some new trigger angles - it seems to get better as I get closer to 90, but if it try to use the + 22.5 like 5 it freaks out and backfires like mad. I assumed if you are going to use a trigger angle greater than 90 you start back at zero and then select the +22.5? Or do you subtract 22.5 from what ever angle you want? (95 - 22.5 = 72.5)

Either way I wouldn't expect the trigger angle to be greater than 90 since there are 4 teeth 90* apart and the trigger angle is the degrees from the tooth to TDC. So why won't it run with a trigger angle of like 2? shouldn't that be very close to the same setting as 90? Maybe i'm thinking about this wrong...

*EDIT* - or wait, in crank shaft degrees there should be 180* between teeth. hmmm...

**Zach** · 8-29-09, 21:41

yes, it's 180. I believe my trigger angle is 60 or 61 degrees, but I'm using the GT distributor.

**n2o_matt** · 8-30-09, 16:32

IDK, but anything past a trigger angle of 90 ad it freaks out - backfires ect

**Matt Cramer** · 8-31-09, 8:36

If you actually need more than 90 degrees of trigger angle, you will need to use the Trigger Angle Addition setting.