fried coil

[andreNL]

hi Mattias thx for the reply   

yes i do have a timinglight but its broken 
and my engine istn running so its useless anyway 

if you can exactly calculate ignition timing you dont have to worry about that
during tuning your fuel requirements and cranking and priming.
Its like rulling out timing issues and focus on fuel requirements and other settings
a DIY VEMS enthusiasts encounters.

I will update my firmware when my hardware is working well
if i update now i don not know if a certain problem is software problem or hardware
with my 'old' firmware i now 

[mattias]

It's impossible to exactly calculate ignition timing from rotating the engine by hand, the error will be a lot higher than 0.25 degrees and I don't have to tell you how bad that is on knock-limited turbo engines. Sure, you can tune and listen for knock and get best torque on a dyno - but you won't know what exact timing you ran if you never used a strobe light to check which makes any numbers in your ignition table suspect and useless for comparison.

A timing light is the only way, if there was another way  it sure would be a revolution.

[andreNL]

Oké i will set ignition with a timinglight once engine is running like you said.
Cheers andré

[andreNL]

Well got sparks again 
soldering at -8 degreees is not nice but it works again sparks on all cilinders
with a dizzy setup using 23-39-7 as tooth table and trigger tooth 7 after de missing tooth.
but now other problem  my 3th injector is flowing fuel in closed position 
i know its closed because when i open it manual in Vems it sprays loads of fuel extra and
is clicking. it looks like the needle seat is leaking so much its even dangerous for my engine.

Lucky i have a spare injector gonne replace it tomorrow.

[andreNL]

Hi All 

Inspring weekend for me, trying to start my engine
but my injectors where broken. i bought 2 bigger from ebay wich should
balanced cleaned and seals renewed but two of four didnt close properly
and where flooding my engine 

I had a spare set of smaller injectors same high impedance and connectors wich are oke 
so thats working oke now, i'll source down some new bigger injectors later this or next year.

i also did some theoratical thinking about how vems triggers ignition and injectors.

I have a 24-1 trigger wheel
The sensor is located 55degrees before TDC and the missing thooth is 60 degrees (4 tooth) before TDC
together Piston travels 115degrees after the missing to TDC.

Now if i set trigger theeth to 7 and trigger degrees after trigger tooth in the primeray trigger settings at 115 degrees
and in the ignition tooth table bottom up 23-39-7 then ignition acurs 115+(8x15)+(8x15) is 355 degrees wich is 240 degrees after
the first cilinder TDC and is exactly my second cilinder ignition. (1-2-3 firing order)

if i am wright this is cool because you can exactly time your injection event.
example: 4 cilinder 1-4-2-3 firing order 60-2 trigger wheel (10 degrees tooth distance.)
inlet closes 185 degrees after TDC inlet stroke.
You set your missing thooth 170 degrees after TDC,
primery trigger tooth to 0 (10 degrees later)
degrees after trigger tooth 5 degrees.
Now injection starts at 185 degrees after TDC (inlet stroke)

To get ignition timed to for example 10 degrees before TDC
the piston has to travel 165  degrees is 16 theeth + 5 degrees.
so you set your ignition tooth table to 46-76-106-16
and add 5 degrees to the degrees after trigger tooth in the primery trigger settings. (10 degrees in the setting)

I hope my thought are right, now figering out how the injection table works.
Its working in reversed order but is it following the firing sequence 3-2-1 or ignition events 2-3-1?

Cheers hope my thought are wright and it helps the forum 

[mattias]

I didn't bother making sens of what you wrote.. sorry.

With 24-1 primary trigger on the crank the trigger tooth table is  top to bottom on a 4 cyl engine is always like this : 36,24,12,0
(most put the 0 at the first cell in the table, because it syncs faster, this also shifts the ignition table correspondingly)

You can't time your injection events unless you have cam sync, and that's just the way it is.

When you have your ignition table set correctly, then set the injection table with the corresponding cylinder injector on the same  row as the ignition tables output for that cylinders coil. If you have cam sync, you can then set the injection timing table, which indicates the number of crank degrees after ignition for each cyl, so about 400-450 degrees or so works pretty well for emissions and steady idle, better throttle response.