swinke

Well I have had the E-Manage running on the Z for 3 full throttle runs and logged the data. Here is the outcome based on an accurate WB-o2 logger running at the same time:

1) Even with 95psi of fuel (100% setting on last slider of DFMU) at the fuel rail the factory injectors are too small to deliver enough fuel at 100% duty cycle to keep the mixture below 13.5:1
2) Between 6k and 6.6k rpm the mixture ramps from 11.5:1 up to 13.8:1 (Its about 35deg ambient here today so this is no doubt worse than normal)
3) I am at 100% injector duty cycle from 5600rpm through redline and the injector time cycle window narrows as the rpm increases. This means that I am getting leaner as the rpm increases. The WB-o2 verifies this also. (Can you say "plasma welder" kids?)
4) There is no way that ATI did their homework properly on this kit before going to market with it! Nobody is that stupid, right? They could have done the R&D in the desert on a 115deg day I guess. I am sure the kit would supply enough fuel under those conditions. This is also why the Greddy kits (guessing) come preset at 5.5psi boost.

Lucky me I can ramp the timing with the E-Manage progressively down to -10deg from factory at redline so I don’t burn the tops of the pistons off.

By the way, if you are running this FI kit out of the box and have not taken any measures to correct any of these issues your only a bad run away from KABOOM! W/o an accurate WB-o2 logger your in the dark. You have no idea how dangerous this kit is without additional corrections in place.

I would like to think that the tech folks at ATI really do know what they are doing and the ATI marketing people pushed this kit out the door without consulting the R&D dept. If that’s what happened at ATI, well, SHAME ON YOU! Only Microsoft is allowed to do that!

In a nutshell the 350Z-ATI HO kit in it’s out of the box form will never be safe without additional mods to correct for the fore mentioned issues. I got it all on paper guys. Why doesn’t ATI!

I've got pig farmer friends back in IOWA that know more about thermal dynamics and internal combustion engines than ATI does, at least from what I have seen here.

Wicked4u2c

iTrader: (6)

That's why I have been trying to say many times about injectors and what not. Greddy is the way to go regardless of what people say. Best kit and bang for your buck! I have owned greddy turbo kits before and they are top notch! No need to rush a good kit, its better they work the bugs out ATI just slapped everything together to get the sales which it worked! Good job! But they needed to fine tune little things. But sometimes those little things=BOOM!! ATI has tons of great potential but they rushed it to fast... Greddy, HKS Supercharger (COMING SOON) and VORTECH are the way to go!

LBC TRD

Wicked, your car is so tight!

jesseenglish

Well hate to be the voice of dissention in your rant, but there are many people who have perfect A/F ratios all the way up to redline. Myself included. You might want to look at your fuel line plumbing to see if there are any kinks anywhere. I turned my 5th slider up to 80% one time to see what it would do and my A/F ratios went all the way to 9:1. I know there is plenty of fuel available.

You might want to look at other things that could cause this problem.... Kinked hoses, dirty fuel filter, clogged injector.

It could also be a problem with your FMU. Possibly your FMU is not calibrated properly, vacuum line has a leak or is kinked, or even a bad FMU.

I'd take a look at other things because this is the first time I've heard of with the FMU not being able to supply enough fuel.

swinke

You need to concider that the Greddy kit is lower boost because of these issues. Both the ATI and the Greddy kit need serious mods to achieve the higher HP levels that we all want. The Greddy kit is not the HIGH HP solution either. Its just safer.

swinke

My fuel pressure tap is on the fuel rail! Its reading correct. Is it possible that Nissan used 2 different sizes of injectors on this car. Maybe they changed sizes during the first production run of the car. What is the production date of your? I will check mine and post later.

GaryK

Swinke, I'm not here to get into the ATI is good/bad argument. But, I do have a suggestion...take it or leave it. If you have the dfmu slider all the way up at 100%, you should be getting more than 95 psi fuel pressure. I'm pretty sure that is where your problem is. Check out the fuel system to see if you can find anything. At 100% on the dfmu sliders, you should be at about 150 psi fuel pressure.

For reference, my last slider is at about 80%, and it never leans out even running up to 7100 rpm. I hold a/f ratios at 11.5 up to redline.

Oh yeah, have you verfied that the last slider is actually active by watching the led?

BTW, dare I say...it's official, you've jumped to the same conclusion as everybody else before they verified what the real problem is

jesseenglish

I'm not saying your Fuel Pressure isn't correct, and honestly I wouldn't even be able to calculate what FP you should have for a perfect A/F ratio at redline, but I'm saying it could be something else.

You're living dangerously by allowing the car to run at 13.5:1 A/F ratio, so you really should look at everything fuel and FMU related to make sure it's all plumbed properly etc. I'm just hoping it's a simple fix for you I guess.

I don't think Nissan changed fuel injectors because if you go to purchase injectors, there is only one part number.

swinke

My last slider comes in at about 5.6psi. I read the instruction.

jesseenglish

If the FP that Gary says are correct, then your FMU isn't raising the FP high enough for some reason, or there is another problem not allowing high enough FP at the rail. I'd open up the hood and look for kinks, pinched lines etc.

swinke

There is certainly something different about my car and yours. Not to metion your at high altitude, right?

GaryK

Sorry...so are you saying that you see it come on when your boost gauge hits 5.6 psi? I can't tell from your post, but you have to verify this using an accurate pressure source and also verify that you see it come on while driving. Getting that scale adjustment set properly is a must before fine tuning anything else.

If all is well with that, then I'd start checking the fuel system out...lines, filter, etc.

jesseenglish

I'm at 4600 ft, but you still should not have to turn your slider up to anywhere near 100%

swinke

I have a Snap-On 5" pressure guage for testing low pressure sources. Its accurate! Well it better be for $60.

jesseenglish

Gary brings up a good point. Just because it was calibrated properly, doesn't mean it's working that way while driving. Unless you're watching the LED's on the FMU while you're driving there is still the possibility that the boost sense line going from the plenum to the FMU is pinched or there's a leak not allowing the FMU to know how much boost you're actually running.

swinke

I use a small handheld radiator pressure pump as the source and bleed slowly down to the pressure I am looking for to do testing.

GaryK

Cool deal, if the last band is active when you are driving then it has to be in the fuel system itself or the pump is not getting up to the correct voltage. Like Jesse said, it could be the fmu. Can you log the voltage output to the aux pump? You might see something there, like no voltage increase when the last band goes active...

swinke

In some circles this may not matter but I design and build broadband CATV systems for a living. The details that have to be observed in my daily work life are finite in comparison to the crude matter of tuning a FI, computer controlled, fuel injected car. I have checked everything mentioned in this thread at least twice before today. I did the install myself. I am very **** about most things I get involved in. My technical acumen far exceeds 99.9% of the people I meet in my field. I am certain I have not left out any detail that would cause this issue. There is something very different about my car/kit than yours, obviously. Let’s try and figure out what it is. EJ has this very same issue. It’s not just me here.

jesseenglish

EJ's A/F ratios are fine, he gets detonation because of timing.

swinke

I will try that. That’s what I was looking for. Hadn’t thought of that one yet.