Twin Turbo Dime

Datalogging:  8.13.2025 Early datalogging.  Zero tuning done at this point, it's literally load the base 300ZX (Z32) map, scale for the 740cc injectors (getting dead time is important!) and drive. Datalogging under normal driving didn't throw any flags, but also it never gets much more than 20% throttle and 2500rpm - there's enough low-end torque you can just short shift it all the time. This chart is gears 1-4, but never using more than 60% throttle and not going past 5,000RPM Crunching "speed per 1,000rpm" for each gear (I'm a numbers dork, it's what I do), we come up with  * The 2 nd gear plot is 30 – 52mph and the elapsed time is 2 seconds, which calculates to 0.5g acceleration – not bad for just over ½ throttle in 2 nd gear. Over the years I have crunched numbers and have figured 0.6g is probably the upper limit for Red with street tires (SR’s and other lighter 510’s will fare better). More parsing of this chart gives me: *  30-72mph in 5.0 seconds ...

8.11.2025:  Checking WB02. Thirty seconds of steady state, third gear, 1400-1500RPM, 16-19inHg vacuum, 5-7% throttle. Top has Throttle, RPM and manifold pressure, bottom has left and right bank WBO2 reading

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 ...

Minivan mode at 60mph, just wind noise Loud mode at 60mph  

  This page will detail the various Nissan twin-turbo (VG30DETT) swap-specific items. The main thing of note here is the downpipes. While we were able to retain the stock VG30DETT exhaust manifolds, the downpipes has to be custom-built to fit into the smaller 510 chassis These actually went through a couple iterations. This is version 1 of them circa 2004. Note the driver's side has some nasty bends in it.  Even with this the car put down over 330hp to the wheels (per Dynojet) with stock everything (turbos, intercoolers, etc. In 2009 I upgraded the turbos to still small Garrett GT2554 units, and with that change came a redesign of the downpipes as well. Another thing done initially was to use the factory Nissan intercoolers

  Items on this page may be sorted later, but I wanted to have some log of minor changes made along the way. Overflow hose changed from rubber to a hardline