Technosquare says rich

http://www.technosquareinc.com/350z.htm#features

Fuel Map Adjusted
Stock fuel was set to detune the top end horsepower. We discovered that the car runs extremely rich after 5000 rpm. Air to Fuel ratio (A/F) of 10.5 was found right before the stock rev limiter kicks in. Cleary, Nissan was trying to detune the power output at higher rpm to discourage the driver from hitting the rev limiter. For the performance enthusiasts, however, this is unsatisfactory, so we set the A/F to 12.5 all the way to redline to provide adequate power gain while still maintaining a safe margin.

but

AAM says lean under wot

http://www.alteredatmosphere.com/350z/350z_13.asp

One of the simplest ways to upgrade the performance of your Nissan 350Z or Infiniti G35 is to have the factory computer reprogrammed for optimal performance. The Nissan 350Z and Infiniti G35 run extremely lean under WOT (wide open throttle) from the factory. Through enhancing the ignition timing map, adjusting the fuel map, eliminating the speed limiter, and raising the REV-limiter to ~7100rpm our customers enjoy more power, economy, and reliability. Expect a gain between 8hp and 16hp depending on the vehicle.


both are trustworthy around here and have both done R & D.

any other opinions?

can ya tell i want a reflash.

 

Most Z's start out lean then slowly drop to richer conditions at WOT. This has been shown to be the case in many independent dynos. Mods will usually lean out the A/F mix a little with the ECU trying to compensate for it. At some point though the ECU cannot make the neccessary corrections and you need a reflash that overrights the stock fuel maps and add more fuel.

With the parts you have I would get a dyno performed and see if your car needs a reflash. Headers and especially cats make the biggest changes to leaning the A/F mixture. Right now, you might just be in the sweet spot of 12.5 to 13.0 throughout the powerband A reflash would just make your wallet lighter

 

im pretty sure im running rich. tons of black smoke comes out at wot.

if i had headers id be in the same boat as you w/o the reflash tho.id love to have 283/266. maybe when i do headers and cams. ive just heard headers cost too much to install so id get both done at the same time.

thanks for the post.

 

My car stock was rich. As I modded I became very, very lean. Over 15:1 lean on the dyno....some ecu's can handle mods, others like mine, do not compensate for them. I have seen a Z with all the NA bolt-ons AND cams with a stock ecu running a nearly perfect 13:1 a/f putting down around 290whp. Every car is different, but overall Id say with mods they start leaning out.

 

Here is a list of my performance mods and attached is a dyno on a very hot day here in houston (102F!)........can you guys comment please? Would you recommend a reflash to improve the a/f ratio?

2004 G35 Coupe AT
K&N Filter
ZTube
3/8 MD Plenum
10-Wire GroundKit
UR Crank Pulley
DC Headers (Ceramic Coated)
Crawford CATS
Injen Exhaust

 

i'm not an expert, but it looks pretty good to me, leaner early, then mid 12 up top. they might be able to do something with your timing, tho.

 

Powerband looks good, as does AFR. In fact, the only places I see where it slightly dips down are between 2.0-3.5 and 5.0-5.5 (where the powerband and AFR dip down). That could use some slight leaning out, if you are really striving to improve it.

 

I'm almost up to 14 between 4500 and 5600 with it gradually climbing down to 12.9 by 6300

Also, I'm at 15.1ish at 2750 and straight down to 13.1 at 3000....

Should I get a reflash?

 

shooter and dom, you guys are jacking cu's thread...should start your own.

 

CUxtopher I apologize..........didnt realize i was jacking ur thread.

 

If you read more carefully, AAM says that stock, they run lean at WOT... then they go on to say that by enhancing the ignition timing map, adjusting the fuel map, eliminating the speed limiter, and raising the rev-limiter...... frees up more power.

Its kind of confusing, but my take on it is that they are saying the cars run lean stock... so they make the car run richer, freeing up more power.

So... if im right AAM and Technosquare are saying rich is better.

 

i found this graph helpful.

 

I got a question why is it so much to do a flash on the Z???

 

Customer base is much smaller than other cars.

 

Which one would u guys recommend technosquare or AAM?

 

I haven't taken my car to the dyno yet with all my mods.

 

anyone know if a flashed ecu can be implanted into another car with the same model yr/transmission?

 

yes you could but i think you have to get some code from your ecu flashed onto the new one for it to work on your car. i think there's something about it on the technosquare website

 

I think it can, BUT you have to have the Immobilizer removed from the ecu. Your Z key has a chip in it, so for example if you put my ecu in your car your car shouldnt start cuz my ecu is looking for a signal from my key but wouldnt get one because yours is in the ignition. Im pretty sure Technosquare can remove this altogther and have another Z's ecu (your year) work in your car.

 

I agree. My 05 started out running rich. By the time I was done modding a few flow mods, my car ran 15:1 on the dyno.

My first reflash put me at 14:1 ish.

I'm hoping for 13:1-13.5:1 on my next reflash.