Twin Turbo Datsun 510 - powered by 300ZX: Early acceleration datalogging

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 2nd 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 2nd 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 (the 2nd and 3rd gear pulls)
* 10-85mph in 11.5 seconds (full chart from 1500rpm in 1st to 4300 in 4th)

Air / fuel ratios look good, although above 10PSI it does get richer than the target map wants, but I'm certain it's an enrichment setting - just turn a dial someplace.

With, no boost controller currently connected the 17PSI is a little more than I plan on running. (15psi) but not dangerously so, at least not the very short periods it's up there.

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