Robots don't know the difference between days of a week. The build tolerances for these motors are extremely tight, so the margin of error is slim. I just think the OP's car is in bad shape and he can't tell - probably in need of new filters, and just some general maintenance.

 

stock to stock 350z's really don't dyno all that different. Different dynos are the culprit.

No two dynos will dyno a car exactly the same, least of all a dyno jet. Depending on calibration you can make the numbers way high or way low.

 

Good post. Imo, 1/4 mile trap speeds, and to a lesser extent 1/4 mile times, are the best way to judge a car's performance. If it's trapping 100-103MPH, which is typical of a Z (and will vary between a mediocre to solid launch), you've got a healthy car. That's just how I look at it.

 

I have to disagree. Sht track prep and high altitude tends to show otherwise. Our fastest NA Z in Vegas ran a 13.766@98.31. Hell, I haven't broken into the 100+Traps and I'm supercharged at 5Psi on my roadster...granted I weighted in at 3850

 

From that time we can conclude that it is indeed a healthy car, though, which is why I said the time matters also, to a lesser extent. In case of a 14 second run, the 60ft is ideal in determining the correlation. The numbers on a slip tend to tell the story better than a dyno can, imo. Like I said, that's just me.