InputTrigger/HondaFTwentyTrigger (2011-07-25 19:27:23)

Honda F20

From the S2000, this is now a popular engine conversion into older cars and Lotus 7 replicas as it is an RWD engine.

P1017888.jpg

There are 12 equally spaced teeth 30 degrees apart, with an additional tooth positioned ~20degrees after one (~10degrees before the next).

The engine turns clockwise (apparently this is the only Honda VTEC engine that does) so the trigger pattern is:

..., 30, 30, 10, 20, 30, 30, ...

Suggesting that this trigger cannot be used with InputTrigger/ShortGapTrigger (See below). Missing tooth with advanced filtering, setting missing tooth threshold between 1.5 (30/20) and 2.0 (20/10) could work, if it starts with 1.75 it will run too (the wildest relative acceleration happens during cranking, because of the low RPM).

Maybe the trigger could be turned over and refitted which would give the pattern: ..., 30, 30, 20, 10, 30, 30, ...

Now the proper 30, 30, 10,20, 30 ... setup is implemented (along with any similar "extrapulse setup"), also with camsync in 1.1.96. Now under testing.


did you try with missing tooth setup

If gaps are 30,10,20,30 than a variation of InputTrigger/ShortGapTrigger that is not yet supported, I think (because it would also require shortgap at the next event to be fired, 180 degrees later in a 4cyl)


TODO: Configlets should be made for:

In factory applications the missing tooth wheels are better choices (and actually mostly used: better timing and diagnostics can be achieved without stricter wheel-precision requirement), but for home-made setups the low toothcount (often bolts) are usually appealing.