Fitting a Cam sensor
Turbo Mini Forums

Can anybody advice me on how and where I can install a cam sensor on my 7 port 8 injector build. I'm looking for a light weight solution. I assume I can use either use the dizzy drive, fuel pump hole with a modifaction to the cam or fit a sensor to the timing cover?

The timing cover would be my preferred option.

I plan to run the 1st injector bank fully squencial and then 2nd bank grouped that activate above a certain rpm and throttle angle. The emerald K6 ecu as 6 injector drivers according to the manual will support this.

Edited by alaskanow0 on 8th Jul, 2015.

Class C 3rd Place Avon 2011 14.18 @101mph

Turn the fuel pump lobe off the cam and cross drill it for a grub screw in the correct position.

Then an aluminium plate across the hole in the block with provision to mount the sensor.

The above would work fine. Or no doubt you could maybe use the lobe itself alone with a hall effect sensor..
If the lobe has no abrupt points, you could drill/tap and screw in a short grub screw into the highest point to create a tooth.

or at a push, as a temporary measure a year ago I bodged a cam sensor into the valve cover of my V8, with the hall sensor pointing at the tip of one of my rockers which worked pretty well.

You'd need to check with Emerald, but most ecu's should allow the tooth to be anywhere in the 720 cycle, you just tell the ecu where it is relative to TDC so it then knows which is cyl1

9.85 @ 145mph
202mph standing mile
speed didn't kill me, but taxation probably will

or if your using the fuel pump as a drain...

tap the back of the timing plate and put a bolt in the cam gear, Paul S did this I belive,

or, drill and tap the block behind the dizzy cog and turn that off for a grub screw.

Yes, done this a few times now. Made a couple of cam sensors from dizzies.

Preferred solution is, as Joe said, threaded hall sensor through the back of the timing plate. Use an alloy vernier duplex and swap one of the stainless steel screws on the pulley for a steel one and jobs a good 'un.

Biggest issue is sealing the threaded sensor to stop oil leaks.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

if you do drill/tap cam sprocket one thing to watch out for is dont use an alen cap head bolt as ive had trouble with it giving two signals really close together

so a solid slug of something would be my choice or tigweld the center up

yet to get back into the mini but when i do this will be one of the things i want to sort out


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I use the dizzy drive with a machined down dizzy body, cut down dizzy shaft with a slotted wheel mounted on it and an opto switch.

But that certainly doesn't satisfy your criteria for lightweight.
But it is very simple and very accessible (which the back of the block or timing chain won't be).

First thing to check if you want to consider something that is already there - like the fuel pump lobe - is the EC requirement for trigger angle.
You may not have the full 720 degrees available to chose from, on mine it's pre-defined as being approx 30 degrees before the 36:1 wheel missing tooth, ie 120 BTDC

If you use a hall switch (which is by far the most common choice) bear in mind they prefer sharp square edges to trigger off. That's not to say they won't work on a sharp round edge (like a grub screw or caphead bolt) but all the datasheets I've seen quote the test data from a square edge.
Rover just milled a slot through the (not required on an MPI) fuel pump lobe so the sensor was picking up a much more Square edge because it was reading sideways through the slot. Plus they used a VR sensor which doesn't pruduce a "sharp" trigger anyway.

Final point, for fuel pump or back of timing chain you will have to come up with a good way of sealing it to stop oil leaks and pick a sensor designed to run in hot oil.
The common ones sold for use with aftermarket ECUs will obviously satisfy that but if you're looking for maximum weight saving I'd pinch one from a modern car that has a moulded plastic body and runs in oil, most of the common crank sensors don't but some cam sensors do, ie my Mondeo where it goes in through the front face of the head and reads of the front camshaft, it sees a lot of heat and has an O ring on its shank to keep the oil in.

If I was doing it again I'd use one of them in the back of the timing case plate but use a hexagon head bolt aligned to present a square edge.

Schrödinger's cat - so which one am I ???

Great info guys. I'm using a alloy simplex and DSN billet cover (weighs more, but less prone to leaks).

Any recommendation for the sensor, ie part numbers / links etc.

Class C 3rd Place Avon 2011 14.18 @101mph

If you can get away with an OEM sensor, then it should be more reliable as it's being used in the environment it was designed for,

But a lot will depend on type of fitment you need.

9.85 @ 145mph
202mph standing mile
speed didn't kill me, but taxation probably will

Guys, bringing this back up as I may need a cam sensor on my MPi block. can't use the cam sensor position on the back of the block as the turbo is in the way, so looking at other options.

So going on what's been said above, would it be possible to put a single channel hall sensor on the outside of the timing chain cover (got a DSN one so could have a Tig welded mounting), change 5 of the bolts to stainless and one mild steel and get the signal that way?

In principle, yes.

Things to be aware of,

1, as per Josh above a caphead screw/bolt might give a double pulse (not all ECUs like that)

2, ideally a hall sensor likes a square (ie, parallel) edge rather than a round cap head screw so a hex head bolt aligned correctly would be better. Also most of them like the "height" of the "tooth" to be at least as high as the "width" of the "tooth".

3, not all stainless materials are truly non-magnetic so check the grade you want to buy against whichever Hall sensor you intend to use.

Having said all of that, modern hall sensors will detect pretty much anything, they have to, to preserve OEM warranties......

Schrödinger's cat - so which one am I ???

Depends on the vernier duplex but mine have always had stainless screws so I changed one to HT steel. Stainless is not detected by hall sensor.

Hall sensor through the back of the DSN cover picks up the end of the screw so no issue with double pulse.

Done it twice now - works fine, just worried long term about oil leaks.

I'll try and find the pictures.

Edited by Paul S on 26th Jun, 2020.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

Edited by Paul S on 26th Jun, 2020.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

Schrödinger's cat - so which one am I ???

I meant as A1, A2, A4 stainless, but i guess there seems to be another way of gauging iron content.

Cheers for the input lads, its food for thought, however i seem to have got the Haltech to work on batch firing and wasted spark, so may not even be needed!

Wasted spark is not an issue but batch fuel injection will depend on you setup. A real MPI setup requires sequential (but I don't know if the Haltech can handle the needed sequential injecton timing).

http://www.jbperf.com/