crankshaft trigger vs cas

[Bgtym]

I have tunned many different control units.
and I know the main Nissan synchronization problem
The СAS has huge backlashes, and large backlashes from the timing belt.
(I already created a thread on this forum)
and in my hands was a converter kit from Ross performance. (synchronization from the crankshaft)
this is a perfect example of sync and cas problem (https://www.instagram.com/p/BZNpghRlNaY ... _copy_link)

first I tuned the motor to СAS, after which I installed the trigger on the crankshaft
the difference in the dynamics of the car is just huge
Matt is possible upgrading firmware under the crank trigger?
for example, the vq30 has a crankshaft sensor





rb25det neo
540cc 96%
aem 320 fuel pump
hx35 turbo boost 0.9
https://www.instagram.com/p/CFSR4TGIe1o ... _copy_link

[Matt]

Nissan ECU code runs in a general loop to do normal computation and then interrupt (CAS) triggered code which does timing critical operations for fuel and timing.

The fuel and timing operations are done in external chipsets, and given parameters (such as dwell charge time and trigger time) by the ECU code

What I'm getting at here, is that the CAS inputs trigger the interrupt code to trigger the rest of the operations. It is not possible to modify the ECU code to use crankshaft trigger this way.

Some kits use the crankshaft inputs to trigger the CAS via emulation. Last time I looked into this, there was no ECU code modification required but the kits were over the $1K mark so not really worth it, considering you could use the funds to put to an aftermarket unit

[Bgtym]

thanks for the complete answer Matt
one more question)
if you make a disc 180 marks on the crankshaft,
and transfer the 1 degree signal to the crankshaft?
can such a scheme be workable?

or leaving a signal of 120 degrees on the camshaft is all useless

[Matt]

If you can emulate the same signals seen at the camshaft, from the crank shaft then that is definately an option

I've made a CAS simulator for my bench (and CAM simulator) by putting in an RPM signal and then it gives me the 1 and 60/90 deg outputs. If there was a way to convert from hall effect crank signals to CAS accurately, then that could be a interesting project

[tyndago]

It would be cool to have some kind of crank trigger. Maybe even something that will read off the cam. As long as you keep adding features to the Nistune, I want to use it over some other kind of ECU in most of my cars. I love the way I am able to get a car to run on it. https://www.nzwiring.com/index.php/product/trigger-kit/

[Matt]

Unfortunately the CAS signal in the Nissan ECU is not something we have control over. It is done in the logic chips outside the firmware. We get just get the 'interrupts' which are the signals which let us know when the CAS window opens/closes. Other logic chips use the edges to trigger spark start/stop. The firmware just sets when the ignition starts (BDTC) and duration (dwell) to the logic chips, but the rest runs outside the firmware