Hey guys, I just dyno'd the Z today, and I'm pretty happy with the results.

Nitrous Express Wet Kit
Nitrous Express Opener
Zex Heater
Zex Gauge


Baseline
233.4 HP 225.3 TQ

75 shot 41/24
294.9 HP 332.5 TQ

100 shot 52/31
321.5 HP 387.3 TQ

Need a little help though seeing as this was my first time. My last run with the 100 shot (52/31) was pretty rich, staying between 10 and 11 and bottoming out under 10 around 5500 rpms. How rich is this and can it ruin my car. The shop guy said it was kind rich but shouldn't hurt the car, it just isn't running at its optimal level. I know I'd be only running this rich for the few moments I'm spraying but I don't want to ruin anything. I was thinking about running a smaller fuel jet but how much lower should I go? 1 size?

Any help, suggestions, or opinions are welcome.



302177-dyno1.jpg

 

dyno2



302179-dyno2.jpg

 

It looks to me like you're running an automatic and are initially having trouble with the torque converter... Is this right?

If so, you can throw out that high torque # because you're not reading the cars output, you're reading an error induced by what I think is the phenomenon of the torque converter "slipping". Take a look at the torque around 4000 rpm's and that is the correct torque number to quote.

Also, what type of dyno was it? Did it have SAE Correction Factors? If not, how hot was it when you dynoed? What size tires do you have? What grade of gasoline did you use during the run? How did you break in the car initially? How often do you change the oil?

All of these things (albeit almost negligible) have an affect on your output results. Even though it's not important to most people, I like reading up on that type of stuff when I try to compare 2 different cars that dynoed on 2 different days in separate states.

<font color=blue>The above statements are only my take on the issue. If you disagree with anything I typed then you are 100% right!</font color=blue>

 

10-11 AF is not really that rich, always better to be on the rich side of 12.2 AF than the lean side which will quickly melt things.

The nice loooking torque curve shows the 75 HP jet combo is perfect and pretty safe............don't get greedy.

 

Dynojets are a dangerous place to optimize fuel because they don't load the engine correctly.......resulting in faster than real world acceleration. Carefully find the peak, then back off at least 7-8% of peak power for real world use.

Consider that 33F warmer air will lean the engine by 3-4% even with cold nitrous mixing as outside air is still 70% of oxygen source.

 

I dyno'd it at on a cool night, I'd say around 75. It's a 2003 350Z Base, Manual, 30K miles. The runs were done in 5th gear with about a 10 minute break between the basline and the 75 shot and about 30 mintues between the 75 shot and the 100 shot because I had to switch out the jets. Not sure about any SAE correction factors, it was done in San Diego. 91 oct gas was used. I broke in the car nice and slow never going above 3500 rpms. I believe it was a dynojet, not sure what model or anything. I change the oil regularly. I have the stock 17 inch wheels and tires. I think that covers everything.

As for getting greedy, going to 150 shot or higher would be greedy seeing as theres a few Zs and Gs taking it to that level. I want to keep it at 100 and just get it running right.

 

Then drop your fuel jets one value at a time till you get the AF you want............see 10:1 AF is protective incase something goes wrong like the fuel or fuel pump.

One mistake [too lean] and the rings and ring lands on the piston will go. Heck they may fail anyway from the abuse [more BMEP] than design reserve. Without the ability to decrease ignition advance [4 degrees for 100 shot] you are getting in risky territory.

Keep ant eye on #6 and #5 static compression for early signs.
Just trying to avoid you having to buy a new engine sooner than you would like.

Infiniti corporate is getting good at spotting nitrous and supercharger non warranty failures now.........as there have been so many [more than 1or 2].

How many 150+ runs have they logged is the question: 3-4 or hundreds?