38 replies to this topic

[Spider]

Hey guys,

 

I'm just toying with a new Ignition System, for which I need to fit up an angle sensor for. I can run with a Crank Trigger (and a wasted spark set up), but just wondering if anyone has done a Cam Angle Sensor and if you'd mind sharing how you did it and thoughts / impressions of it.

 

Cheers,
Chris

[sonscar]

Do you need to know the angle or just the stroke?The distributor is used in some aftermarket conversions.Steve..

[Quinlan minor]

I believe that the reason that a crank sensor is used, nowadays, is that, because the crank/piston relationship is pretty much direct, it's as accurate as possible for ignition timing.

The camshaft, on the other hand, has all sorts of lash in its connection which, along with the gearing, makes it a far less exact source of data.

[nicklouse]

I am sure you could get a pickup from the big sprocket using a modified CNC. Timing cover to hold the sensor.

[Avtovaz]

whats the ign system you are playing with? I think the cam sensor is only for working out the phase of the engine, so then you can do some firing of injectors in certain ways.

 

Ive got the b230 running in my bmw on injection, its got wasted spark, and the injectors fire in pairs at tdc, if the cylinder isnt firing the fuel just sits there happy on the back of the valve until the next stroke.

 

 

Cam sensor on an A series does seem a lot of work..

[Steve220]

Moke, I'll try and dig out the article and pics from the turbo forum. It has been done from a modified cam pulley and timing gear housing (as Nick points out). Great for fuel injection ??

[Mini Manannán]

I thought you only need cam timing if you're doing EFI and that a crank sensor is enough for ignition?

[Shooter63]

Cam sensors are for full sequential injection and COP set ups, used by the manufacturers for fuel economy and emissions, I can't really see the point of them for our sort of engines, even my kit car engine ( turbo, fuel injected) dosent run one. The good old crank sensor will be hunky dory

Shooter

[Spider]

Many thanks for the replies and your thoughts here guys.

 

The System I'm looking to fit up, while it will also do Injection, I'm only intending to utilize it's ignition system at this time.

 

I'll be setting that up as a COP arrangement as I'd like to do away with Caps, Buttons and HT Leads altogether.

 

I can do a Flywheel Pick-up easy enough but also want to consider a Cam Pick-up as an option to try. The Flywheel (and any crank) Pick-up would of course work as a Wasted Spark arrangement, and I was looking to get away from that, though, I don't think there's much of a down side to it.

I see the MPI has some kind of Cam Sensor. Anyone know anything about these  ?

[AKat]

Simplest way to pick it up from the cam is the same way the original engine management system on the A Series did...... Dummy distributor driven straight off the gear on the camshaft, hell you could even put roller bearings in it and do away with the bushes altogether.  Very simple to make, plenty of guys have done it in the past.  For best results start from scratch so you're not restricted for space inside the "dizzy" body
 

[sonscar]

Use a Hall sensor in the rocker cover to spot the lifter as it rises.Steve..

[Spider]

Simplest way to pick it up from the cam is the same way the original engine management system on the A Series did...... Dummy distributor driven straight off the gear on the camshaft, hell you could even put roller bearings in it and do away with the bushes altogether.  Very simple to make, plenty of guys have done it in the past.  For best results start from scratch so you're not restricted for space inside the "dizzy" body
 

 

 

I did consider this approach, but also like to see what others may have done too. Cheers.

 

 

Use a Hall sensor in the rocker cover to spot the lifter as it rises.Steve..

 

That is a different approach, thanks Steve.

[Spider]

Being a total newbie to this stuff,,,

 

When a Cam Angle PU is used, the Crank Angle Sensor is also still used. The Firing is done from the Crank Angle, however, when starting, the ECU also looks at the Cam PU to index the firing sequence.

 

The Rover MPI works this way and I think most others do too.

 

This being the case, the simplest approach (at least for me) is to fit a PU to an dummy distributor, though, I do also like the idea of a Rocker Sensor too.

 

Slowly getting there !

[nicklouse]

Or go wasted spark....

[Spider]

Or go wasted spark....

 

I'm actually trying to avoid that,,,,