Cam sync confuse me

[PG]

Hi all!

I don't know if i use cam sync with 1 tooth, than the ECU counts all the teeth on primary until the next cam sync sign, or it's just reset the reference tooth table to 0. For example: Now i have 36-1 pri , no cam sync, 4 cyl, wasted spark. reference tooth table 0: 6 , 1:24 that's ok. But i want cam sync, now i have to set reference tooth 0: 6 ,1: 24, 2: 6 , 3:24 or  0:6 , 1: 24, 2: 42, 3:60. does anybody understand me?
The main thing, if i have cam sync, than i have to count the pri double, with 36-1 pri 72? or the same 36 teeth?

Thanx!   

[GintsK]

After cam signal ecu  just waits for next missing gap. Then count from zero two revs. Your ref table should look so (from bottom):  18 36  54 0
It contains zero. Further trigger offset you can configure with first trigger tooth

Now Vemstune has two nice things - visual sync representation. And you can get preconfigured 36-1 or other common triggering systems from drop-down menu at the bottom of trigger window.

Gints

[PG]

Hi!


Thanx, now it's getting more clear. So if i need the first trigger tooth not zero, than just set first trigger for ex. 6 ,than the ref tooth is 24 40 60 6.
Because of some reason, i can't turn the trig.wheel. And it's for just an example. In reality , I have an Aprilia RSV-1000, it's 60deg V2 engine. Odd fire a bit . Last year i used it with wasted spark, but i need more dwell time. My redline is on 12K, and now i must use less dwell, because vems freezing, and stop fireing at some rpm only work again after power off. Now my ref tooth is 0 for the rear cyl, and 9 is for front. First the rear is on TDC after 60deg ,the front. I use ref 0 for rear and cyl.sep. spark delay 30deg, tdc after trigger 65 deg. . If i use 3 and 9 ref tooth,than i can use only 1ms dwell, it's good up to 12k, with 0 and 9 it's ok with 1.8ms dwell.

Thanx for help.

PG
E85 Dragbike Team Kecskemét
Hungary
http://www.youtube.com/watch?v=ZamkDsYRc_I sorry for bad video aspect raito.

[GintsK]

Usually we use zero in one bin of ref tooth table. And do "virtual" disc rotating with first trigger tooth.

If VEMS freazes for me seems it was related with more than one tooth trigger errors. If VEMS saw e.g. 56 instead of 58 tooth, it turns outputs off.

[PG]

Hi!

Oh, than it means the first trigger tooth sad which is the "0" ? I mean if i set first trig 3 than it counts the 0 form the 3rd teeth? and the 0 in the ref tooth table in reallity the 3rd.
The strange is that the lower dwell solve the freezing, so if it can't have the correct teeth counting,than why can it do with lower dwell. And on the sd-log, nothing serious, everything is normal no trig error, etc.

PG

[GintsK]

Regarding ref table and first tooth plays with primary trigger visual. I think this is self explanatory

[PG]

HI!

YES! You are absolutely right. Vhen i did this project, the visual part for pri trigger didn't exist.
I checked it now. Sorry for waisting your time.
Thanks a lot lot lot.

PG

[PG]

HI!

Another silly question. If i change from wasted spark to cam sync, and i have a VE table that worked with wasted spark, then should i double the req fuel or the table? As far as i know, i have fuel every spark, and now a have half amount of spark.

Thanx!

[gunni]

You don´t need to change any fuelling things.

[PG]

HI!

thanx for this. I don't know how vems does fuel things exactly.