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Re: Honda D/B/H trigger patterns

2021-05-12T23:45:23

The schematics that Honda used for decoding their VR sensors is available if you wanted to copy something that's literally been used hundreds of thousands of times. This would mean using the sensors inside the Honda distributor. You'd probably want to run coil on plug since it isn't 1995 anymore.

https://github.com/rusefi/rusefi/wiki/OEM-Docs/Honda/bomarc-services-p28.pdf

You could also reinvent the wheel.

If you wanted to remove the distributor altogether, the epxoy'd rare earth magnet drilled and pressed into the cam gear + bracket for hall effect sensor a la T1 is a pretty clean solution.

Statistics: Posted by blundar — Wed May 12, 2021 11:45 pm

Re: Honda D/B/H trigger patterns

2021-05-12T23:43:47

Thank you for amazing content.

Statistics: Posted by AndreyB — Wed May 12, 2021 11:43 pm

Re: Honda D/B/H trigger patterns

2021-05-12T23:37:45

If you want to throw money at the problem to solve it, T1 has sold a special cam gear that has 13 rare earth magnets pressed into it for ~15 years. The cam gear has 12 magnets of one polarity evenly spaced for a "crank" signal. The cam gear has one magnet of the OPPOSITE POLARITY for a cam signal. The hall effect sensor included with the kit is two sensors in one - one waveform triggers on "North" and the other output triggers on "South" so that one cam gear and one hall effect sensor (with two outputs) can provide all necessary engine positioning to run an engine.

https://www.t1racedevelopment.com/product-category/default-category/category/universal-parts/electronics-1/t1-cam-trigger-kits/

Statistics: Posted by blundar — Wed May 12, 2021 11:37 pm

Re: Honda D/B/H trigger patterns

2021-05-12T23:29:18

One partial solution is the CKF or Crank Fluctuation Sensor.

This sensor was added to some US market OBD2 vehicles. The CKF sensor has the same waveform as the CKP (crank) sensor, i.e. the high tooth count engine position sensor. It is thought that the CKF sensor was added to aid in misfire detection. The CKF sensor is a VR sensor that is driven off a 12 tooth wheel mounted on the oil pump. This setup was available for sure for B series engines. A similar but different setup was used on late (00-01 ish?) H series engines. these engines came from the factory with only CYP and TDC sensors in the distributor (2 wheels vs. 3) and the CKP/crank signal came exclusively from an oil pump mounted gear, CKF style. The CKF style sensor is greatly preferred over other style sensors because of the excellent fitment and direct mounting to the crankshaft, eliminating possible sources of error.

The "newer" B series oil pump for 98+ vehicles can be fitted on earlier vehicles. I'd recommend a NEW oil pump but the other components (bracketry, sensor, etc.) are pretty safe to junkyard. I've never seen one of these fail.

This picture shows the CKF pump and bits fitted onto an OBD0 JDM B16 by Zach Hoobler. Note: Zach removed a tooth so that the engine could sync up enough to run without requiring additional sensors. The original 12 evenly spaced tooth wheel does not allow rusEFI to detect where top dead center is without the use of another wheel.

Statistics: Posted by blundar — Wed May 12, 2021 11:29 pm

Honda D/B/H trigger patterns (Most Distributor Hondas)

2021-05-12T23:22:42

Distributor Hondas present a slightly unique challenge for rusEFI. From the factory, 88-01(ish) D, B, H and F series engines came with distributors with ***3*** VR sensors inside. One wheel (crank / CKP) fired at 8 or 12 pulses/crank rev (16/24 teeth in distributor, spinning at camshaft speed. 95+ vehicles use 24 tooth, 88-91 16). One wheel (top dead center / TDC) fired at TDC of each cylinder, 2 pulses per crank revolution, 4 teeth on cam wheel. One wheel (cam / "snail") fired once per revolution of the camshaft.

MRE does NOT have multiple VR sensor interfaces to be able to deal with OEM sensors.

Also, the "snail" shape cam wheel presents some challenges for some of the most commonly used VR sensor interface chips in rusEFI ECUs.

Statistics: Posted by blundar — Wed May 12, 2021 11:22 pm