3.0 Litre Update

So the big tooth is to make it up to 20
That diagram shows 19 teeth btw
:

No it doesn't, the big tooth is two teeth, there are 20 teeth and two missing. I can' then call the missing teeth no teeth, cos they don't exist It all still has to be counted...

A tooth is a tooth even when it's a big tooth The flywheel has 19 icle teeths + 1 big one but it makes 20 gaps

No, the big tooth is two normal teeth. Does that make the sequence only 20 teeth long, because the missing teeth don't exist?? How does the ecu look for two 'missing' teeth, when there is no gap inbetween the two missing teeth to differenciate.????

Understand?

Theres the two missing teeth!

It works without machining the flywheel much as the standard ECU does....if it was all so very difficult the standard ECU would have the problem of teeth and gaps and other dental matters! Lee, dont machine your flywheel (I'm assuming you were taking the p when you said you already had!?) its an extra waste of money!

No ...............there's the gap in the teeth
Showing a linear diagram confuses the issue as there will always one less gap than teeth

It works without machining the flywheel much as the standard ECU does....if it was all so very difficult the standard ECU would have the problem of teeth and gaps and other dental matters! Lee, dont machine your flywheel (I'm assuming you were taking the p when you said you already had!?) its an extra waste of money!

Take the "wee wee" !! Me

[stephendell]

I was looking back through some old emails to DTA and found this:

Existing crank wheel is actually 54 teeth, 6 gaps, 18, -2, 18, -2, 18, -2 not 54 teeth 3 gaps as stated previously. (two types available: castellated or drilled)

If correct that makes each tooth at 6 degrees and the gaps at 18 teeth intervals. 18 x 6 = 108.

Coincidence

Yep..

End of the day it works, and shows steady RPM in the software which matches what the engine is doing. The ecu doesnt rely on each tooth/setup/angle to actaually do the fuel/ignition, its just needs a repeated reference 3 times a flywheel cycle to work from. It doesnt matter how it gets to ths point, if its regular as clock work, then its regular as clockwork....

Some flywheel on japanese motors have for instance 5 teeth only on the flywheel, ie, at 5, 18, 45, 200, and 300 degrees. Completely odd, but if you set the software up, it still fires in a regular 4 cycle pattern. Just because the teeth are in weird configurations it doesnt mean its going to fire at those times, or upset it. It just needs to see a duplicated pattern, and work from that each time as a trigger...

So basically, the ecu works out ITSSELF when to do the firing, so it can't 'go out' at high revs etc....

I will still be getting my flywheel machined....this new fangled ECU thing is too difficult!!

I was looking back through some old emails to DTA and found this:

Existing crank wheel is actually 54 teeth, 6 gaps, 18, -2, 18, -2, 18, -2 not 54 teeth 3 gaps as stated previously. (two types available: castellated or drilled)

If correct that makes each tooth at 6 degrees and the gaps at 18 teeth intervals. 18 x 6 = 108.

Coincidence

'Snot correct ...............Lightened custom Ali flywheels anyone ???
http://www.cldesigns.co.uk/_vti_bin/GTA ... th%202.jpg

[stephendell]

Great diagram

In that case for the GTA it's back to 66 'theoretical' teeth in a 'full' flywheel @ 5.4545 degrees per tooth.

Does the sensor trigger on the leading edge or the trailing edge?

If the sensor triggered on the trailing edge of the large tooth (which would be teeth 20 and 21 in a sequence if the gap was machined out) then there is 10.9 degrees before the sensor would pick up the trailing edge of the next tooth (tooth 1 in the next sequence). Tooth 22 would then be considered the missing tooth.

If there are three repeat sequences at 120 degree intervals then the untriggered interval = 120 - 10.9 = 109.1 degrees

108 is pretty close to 109.1 so presumably that would still work?

Has anyone tried 109 degrees in the adaptronic?

My god what has my thread become! This could possibly be the least understandable thread of all time!

Its fascintaing stuff....NOT!!!!!!! I was just happy that the thing worked on the standard flywheel.....that was enough for me!

Peter ,knowledge is power is bhp

Turn the key, drive the bloody thing...