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JDM '99 1.6 and timing

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Todd Green

Todd Green

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  • Location:SLC
  • Region:Utah
  • Car Year:1990
  • Car Number:60

So, since I'm no longer running SM and the supply of local US 1.6's has dried up, I grabbed an eBay JDM '99 1.6 which all-in-all is working well(*) (other than the initial nightmare of mating it and the JDM ECU to the stock NA 1.6 harness).   The one issue is that it only made 98 HP on a Dynojet.  Putting a timing light on it, it was at 6* rather than the 10* it should be.  :wacko:   That would explain the suboptimal power.    So I grabbed a slotted timing wheel and maxxed it which brought it up to 9* or  so (one other issue is that sometimes it idles perfectly at 900 or so, and others it doubles that.  You can turn the car off and on and you "randomly" get one or the other) so that made timing a bit of a pain since I couldn't reliably get the lower idle.


Anyway, figured someone here might know why a "99" wouldn't idle at 10* (it uses the same cam/crank sensors as a US 99 1.8).   I have a cold air intake and an RB header on it, but otherwise it is stock.   Well it didn't come with a MAF, so I'm using a US 99 MAF, but none of that should affect timing and AFR's are fine.


Also does anyone know if these support OBD2?  Googling shows mixed results on JDM motors, and for the life of me, I cannot find a wiring diagram for it that shows which pins would be for OBD2.  On the off chance that it does, I figured I could use my bluetooth adapter to get some more insight.




* It also has the 7000 RPM limit of a 99 which is an interesting choice and annoying as I run out of gearing in several places where I didn't with 7200.

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