Pulley Options thick enough for Hall sensor magnets?

[slowsixtyduece]

This may be a shot in the dark, but I'm wondering if anyone knows of a quality, stock sized pulley that has a thick enough "behind the fan belt" back section to drill a 1/8" dia hole about 3-4mm deep? Please see attached pic for an example of what I'm looking for (found on here).

This is for an SDS Hall sensor magnet. My current Berg achiever pulley is questionable. My calculations show that I would only have 1-2mm before there's a magnet protruding into the fan belt

Thanks!

[Piledriver]

What "wheel pattern" does the SDS need? Just TDC?
There are several off the shelf hall sensor setups available, like Marios' hidden setup.

You don't need a magnet to run most hall automotive sensors, the magnet is usually in the sensor, just need to pass some steel by it, a (not stainless steel) setscrew or sawn off bolt will work.

[slowsixtyduece]

What "wheel pattern" does the SDS need? Just TDC?
There are several off the shelf hall sensor setups available, like Marios' hidden setup.

You don't need a magnet to run most hall automotive sensors, the magnet is usually in the sensor, just need to pass some steel by it, a (not stainless steel) setscrew or sawn off bolt will work.

The wheel pattern is simply one magnet wherever you happen to locate the hall sensor (the pulley is then clocked to TDC) and another magnet 180* out from wherever the first magnet was placed. The SDS unit uses a Hall sensor- I dont know if the SDS EFI hall sensor works differently than the average pickup. Do you know?


I was looking at Marios- really nice stuff. However, I dont know if it will work. Maybe some sort of conversion would work?

Here is a link to how SDS does their Hall Sensor:
http://www.sdsefi.com/em4e17.pdf

[Piledriver]

All hall sensors I have ever dealt with act as a switching ground, but some are normally open, some normally closed.

Generally, they pull a signal line pulled up to 5v or 12 via a resistor in the ecu to ground to provide a signal.
You can see how yours works with a multimeter when connected to the ECU.

I built my own using an off the shelf Allegro ATS667 sensor and a couple SMD resistors and caps, stuffs in a 3/8" SS tube about an inch long I later filled with 5 minute epoxy... I think I spent $8, and it triggers off a tiny 32 pitch RC truck spur gear to ~12K RPM+

[foreverska]

There are several off the shelf hall sensor setups available, like Marios' hidden setup.

Mario's hidden setup is a VR. It's hard to find an off the shelf hall that fits behind the pully on the T1 engines. I tried awhile back. If you ever find one notify me.

The T4 kit has a hall but it also has a longer snout than the VR.

[Piledriver]

I dug up the spare sensor seyup I made, it is tiny, cheap/easy to make, and works awesome.
Is also a fully automotive temp. grade sensor, and is very likely what is actually inside many if not most OEM sensors.
The sensor body is bent flat against the leads and the working end points out, this will slide into a 5/16" ID tube.

In either 3/8" tube form or an encapsulated popsicle format (default) it could be made to fit ~anywhere.

[Bruce.m]

What are the surface mount components, values & solder points?
Thanks.

[Piledriver]

What are the surface mount components, values & solder points?
Thanks.

I simply used the "recommended circuit" in the ATS667 datasheet, with a pullup resistor appropriate for the intended voltage.
~5K seems to work for 5v or 12v if feeding an LM1813 via a 1uF capacitor to provide a faux VR signal, an opto input must be setup for the desired voltage as it lacks an AGC circuit as the VR chips require.

I chose the component physical sizes to straddle legs where needed.
(smd parts come in numerous physical sizes from ~fly poop to pretty chunky, like the cap I used that straddles (but does not connect to) the 2 middle legs)

The ATS667 will actually run on 3.3 to 30v IIRC.

About the only issue I ran into is you must be careful to reflow the solder joints to remove any stress if you have to bend the legs after assembly, lest the tinned area pops off and you effectively break the smd component.

It all gets embedded in 5 minute epoxy in the end, oil/waterproof and highly mechanical shock resistant.

From a reliability standpoint, connecting all the components with tiny wires might be better, then embed the ratsnest in epoxy.
(one could also make a tiny little PCB for the circuit, but doing it in 3D is usually far more compact)