Twin Turbo Datsun 510 - powered by 300ZX: Haltech tuning - idle

The base 300ZX idle speed settings give my car a little trouble - occasionally it will stall as I come to a stop (in neutral), not very often, but often enough I am conscious about it.

As my VG30 has a lighter flywheel than factory (12.5lbs vs 23lbs) and a lighter front pulley (3lbs vs 15 for the stock damper), I suspect the less rotating mass leaves less room for error when the ECU is setting the idle speed. I've raised the "warm" target idle speed by 100RPM and it's much happier.

------- 8/8/2025 ------

Idle tuning. The base 300ZX map has this for idle target RPM

The warning icon is there because there are two tables enabled in the Haltech here - temperature and vehicle speed.  Since I don't have the vehicle speed senor (VSS) input enabled, this setting is complaining that VSS adjustments are enabled. The fix
* Right-click on the table, choose "Table axis setup"


Set the "enable axis" to off, 


Click OK and the warning is gone


With this out of the way, my engine is not really happy with the 700RPM settings the factory has, so I added some RPM's. The car is much happier.




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