Trigger related page for MembersPage/DTechnologies/Hayabusa project
I need to configure the firmware for my engine.
Basic info
- 4 cylinder, dual overhead cam, 1298cc displacement
- Redline: 10,900rpm
- Firing order: 1-2-4-3 (inner 2 cylinders and outer 2 cylinders move in unison)
- I have a picture showing the order and (very) rough timing taken from the service manual. I've posted it below.
- crank and cam triggers involved - both are variable reluctance sensors. The 2nd LM1815 bought separately (only 1 LM1815 is populated by default) is already mounted on board (?).
Original Manual Timing Diagram
Unfortunately, this is as much info as the manual can provide. It's great at showing the relationship between the sensors, coils, and injectors...but no numbers to speak of.
Crank trigger
- there are 8 equidistant teeth on the crank
- positions: ... I don't know the timing yet
Cam trigger
- single tooth (natch)
- timing: I don't know the timing yet
How do I figure out the timing? - with the least amount of fuss
We usually remove a sparkplug, and move the car in gear 5 until the given engine is at TDC. Than look at the trigger wheels.
There are often marks on the crankwheel (that can be at TDC or other position in custom-hacked setups)
This is something I've been fearing. I've had the engine apart but I can't determine anything that way because the sensors themselves are mounted inside the covers (valve cover & stator cover). At best I'd only be able to guess how many degree's forward or back they are of the tooth/teeth.
How to I set up the firmware appropriately?
The bad news is that current firmware does not support this crankwheel directly, unless engine is a 16cyl.
Options:
- bolt on another wheel, eg. 12-1 (or 36-1 or 60-2). Feasible ?
- 2003 Hayabusa uses a 24-1 wheel. The wheel is also the magnet wheel for the generator...so it's a bit expensive. The search for a used one has been going on for months.
- Aftermarket options are available. Fast by Gast makes a 2 magnet trigger wheel which is driven by starter gears. Requires entire starter housing to be replaced with custom assembly cnc'd out of billet aluminum...even more expensive unfortunately.
- grind off 1 tooth from crank to get a 8-1 multitooth wheel
- Teeth are very wide. This would definately cause balance issues.
- firmware modification: feasible, but significant table-testing needed
- Considering my inexperience, this might not be the best path.
- Adding a magnets to the wheel and using an aftermarket sensor?