Has anyone had experience of putting a cam sensor on an ajp?

[450Nick]

Just about to look at putting a cam sensor on the race motor to run the SYVECS Ecu on full sequential mode, we have an idea where to put it, but has anyone already done this? If so, are there any photos knocking about?

[a1rak]

Not had any experience in fitting a cam sensor but would it be worth it when you consider the position of the injector relative to the butterfly?

[ridds]

Maybe running 4.2 intakes with the injector pointing down the runner and after the throttles?

[450Nick]

It's not actually for sequential fuelling, its for the knock sensor - to be able to tell which cylinder is firing, and therefore where the knock is coming from, the ECU needs to know the cam position. I'm not sure if we'll run it sequential yet as it won't really make any difference to a race engine.

The current plan is to fit a hall sensor to the underside of one of the rocker covers to measure the presence of one of the cam lobes, though not sure yet what clearance is available. I was just wondering if anyone had looked at this problem and thought of a neater solution?

[ridds]

450Nick said:

It's not actually for sequential fuelling, its for the knock sensor - to be able to tell which cylinder is firing, and therefore where the knock is coming from, the ECU needs to know the cam position. I'm not sure if we'll run it sequential yet as it won't really make any difference to a race engine.

The current plan is to fit a hall sensor to the underside of one of the rocker covers to measure the presence of one of the cam lobes, though not sure yet what clearance is available. I was just wondering if anyone had looked at this problem and thought of a neater solution?

Would have thought sequential injection on a race engine would have been preferred? Better fuel economy, less mass to lug around.

Knock control will really be doing very little if the engine is mapped correctly. An engine during race conditions with known fuel and optimised ignition shouldn't really need knock detection. You may end up with it becoming active after heat soak on the starting grid etc but 99% of the time you'll have decent air temperature, and a good supply of 98+ RON fuel.

How are you calibrating the system? Have you got in-cylinder pressure transducers etc to correlate accelerometer vibration level against cylinder pressure.

For the sensor, could the cam cover not be problematic unless you dowelled it? Not sure how much they move on the retaining bolts.

[450Nick]

ridds said:

Would have thought sequential injection on a race engine would have been preferred? Better fuel economy, less mass to lug around.

Knock control will really be doing very little if the engine is mapped correctly. An engine during race conditions with known fuel and optimised ignition shouldn't really need knock detection. You may end up with it becoming active after heat soak on the starting grid etc but 99% of the time you'll have decent air temperature, and a good supply of 98+ RON fuel.

How are you calibrating the system? Have you got in-cylinder pressure transducers etc to correlate accelerometer vibration level against cylinder pressure.

For the sensor, could the cam cover not be problematic unless you dowelled it? Not sure how much they move on the retaining bolts.

I've heard arguments for and against - The loom and ECU is capable of both, so I'll leave it to SYVECS to set it up for racing. I have heard from somewhere though that having a bit of extra fuel on the off stroke to cool the back of the valve is a good thing in a race car..??

Knock control is a backup more than anything, SYVECS again will be setting it up - and have done this previously on Speed 6 and AJP8 engines to good effect. I'm not sure exactly how they set it up - I seem to remember it was more a trial and error thing using some specialist computer they bolt to the engine which can tell the exact moment that det begins. The engine will be set up to run reasonably safely as I want it to last - but if anything unexpected happens - eg an injector fault, the ECU should be able to identify not just the presence of detonation, but it can (I'm told) instantly shut down this cylinder and put the car into limp mode.

Again, I haven't really read up on the details but belt and braces is always a good thing in my books! I agree, some dowels on the rocker cover to locate it accurately do sound like a good idea - we want to try to avoid modifying the head though, so only the rocker cover needs swapping over if the engine is swapped out.