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Trigger wheel thickness?
fha772 - 6/1/14 at 09:43 PM

Hi all,

I'm just sorting out the size of my trigger wheel for my Mercedes EFI conversion.
I was wondering how thick the wheel needs to be?
I'm assuming 3mm+, does that sound about right to you guys?

Cheers Frank.


matt_gsxr - 6/1/14 at 10:24 PM

3mm will probably work but a bit thicker isn't a bad idea to ensure you get the best sensitivity.

Trigger wheels ones are ~5mm.

It depends on the size of your sensor too (big sensor == wider wheel).


You can't have too reliable trigger detection.


baz-R - 6/1/14 at 10:44 PM

the actual answer would be dependent on sensor and air gap

most use vr type sensors that are simply a rod shape magnet (sometimes pointed) with a thin copper wrapped around it, the wheel tooth changes the magnetic flux and induces a ac voltage as thay pass
the ecu then just counts the pulces and a missing tooth adds a sync point

a rule of thumb was the tooth needs to be steel and be at least the width of the rod magnet
air gap should be kept to a little as possible around .75mm


Irony - 7/1/14 at 09:15 AM

My trigger wheel is 4 or 5mm. It's a pretty heavy duty bit of kit. Its from Trigger Wheels. If someone chucked it at you head it would seriously hurt!


mcerd1 - 7/1/14 at 09:43 AM

Mines from Trigger-Wheels - its 5mm thick
(according to the drawing I did at the time to work out how to mount it - i left a 4mm spgot and it sits just proud of that)




http://i5.photobucket.com/albums/y170/mcerd1/Dax/Pulley-V3-1.gif
http://i5.photobucket.com/albums/y170/mcerd1/Dax/IMG_4565-1.jpg



[Edited on 7/1/2014 by mcerd1]

[Edited on 7/1/2014 by mcerd1]


coyoteboy - 7/1/14 at 10:23 AM

Mine's 5mm, again from Trigger Wheels and using a ford sensor with 0.25mm airgap, mounted on a sexy little adapter made by my father! Currently having misfire issues though and not sure of the cause but the scope shows a beautiful clean signal from the sensor.

Description
Description


[Edited on 7/1/14 by coyoteboy]


fha772 - 7/1/14 at 01:52 PM

Thanks guys, I think I'll go for 5-6mm plate, I've got plenty of that kicking about.

Cheers Frank.