articfury

This may be somewhat subjective, but what is currently the best piggyback Air/Fuel Computer?

Apexi S-AFC I/II
HKS AFR
GReddy e-manage
others?

I am interested in hearing past experiences with these.

Thanks in advance,

JD

articfury

My Z isn't stock. I have a full custom dual exhaust, and am making a decision about intake.

From my, and other owners', results, it appears that the Z, like other current cars, needs a piggyback of some sort to make performance mods beneficial. If someone has information to the contrary, I would be very interested to see it.

Until we have an AEM EMS (long time, and more mods needed), the S-AFC and others are going to be the best way to reap the benefits of these mods. Obviously, a full MoTeC or other EMS would technically be the BEST. So, I should say within reason. Spending $2000 on an EMS and setup, for a car with exhaust and intake, might be a little extreme.

There is the possibility of ECU upgrades, but from what I have seen those are not going to be user-tunable. If your mods match up well to the ECU upgrade, then it is a good solution. Also, it appears that there is still going to be a good deal of a wait before the aftermarket ECUs are ready for prime time.

Thank you for your input,

JD

ITR#203

I completely disagree...if you look at the air-fuel ratios on the dyno for the exhaust from Amuse, you'll see that the 350Z runs rediculously rich in the higher RPMs. You'll see that with Amuse's exhaust, the air fuel ratio IMPROVES to 12ish:1, and stock it's around 11ish:1. Just as a referance, even considaring running rich for protection against pre-detonation, 13.5-14.0 to 1 should be rich enough and 14.7:1 is considared an optimium ratio for air to fuel for max power in a perfect world. Running rich, along with a retardation of timing, are probably the causes of the rediculous torque drop in the higher RPMs for the VQ's. Therefore, I believe that there is good horsepower to be found with a air-fuel controller. Unfortunately, you might as well wait for a reprogramed chip b/c an air-fuel controller will do nothing for the timing.

About gains seen on other cars, that doesnt really apply here. Every car is different. For example, even within makes, a ITR gets great gains off switching to a JDM 2.5 collector header, while a S2000 doesnt get crap off the header, but gets great gains off intakes.

Also, air fuel ratios are a situation where it will probably make more difference stock than with bolt ons b/c every bolt on makes the car run leaner and all cars from factory run rich, not lean. How rich it runs from factory will determine how much gain. Just as how much an engine will gain off bolt ons will change depending on how good the factory intake, headers, and exhaust were.

I really hope there will be a cheap fix for the lack of high rpm torque cause you're really not utilizing an engine's torque to it's maximum capability if it's not in the upper parts of the car's rev range.

Alang

iTrader: (1)

I think the initial question posted is legitimate even if you don't agree with the applicaiton.

I too am interested in options of folks that have actually installed/used the various controllers. I will probably be installing turbos once the field has played out a bit, and one of the (IMO) necessary components is Air/Fuel control. ECUs are a good start, but the fine tuning a seperate unit provides is really nice so your car is tuned for your mods.

I have seen a lot of postings on the SAFC on TT.net, but I personally have not see much about Greddy or HKS (nor have I looked much yet). I think Blitz also makes quality boost and Air/Fuel controllers.

Anyone with real world experience with these care to chime in?

Monkey Man

IMO, 11.7 is still way too rich for a NA car. I spent hours tuning my last car with an FJO unit to reach a 12.5 ratio, under boost, 13.5 off boost. Above 13 will still be plenty safe, and will also generate more power. BTW, I ran a stock Honda engine (10.2:1 compression) for a year @ 10psi, with absolutely no problems. If you can't run a stock engine over 11.7 under load, then something is very wrong.

-Jeremy

articfury

Regardless of one's opinion on the benefit of these systems, as I originally asked, I am really interested to hear what members' personal experiences with these devices were.

I am kinda leaning toward the GReddy e-manage, it seems to have the most flexibility. Has anyone heard when the Software Tool will be available?

Thanks,

JD

n3985

So let's all agree that without FI, a piggyback is really not necessary and the benefits/gains will be minimal.

articfury

See my last post...this thread is not about whether you think it will do any good.

If you want to discuss the merits of using one, start your own thread.

JD

NightRider

I once had the Apex-i S-AFC on my Maxima. I gained very little to any power at all. With an intake and exhaust system, I could play with the fuel curve a little bit and gain some lost low end torque. But that was it. Also, Nissan's ECU is a learning ECU. If it sees a pattern of MAF signals, it will adapt to those signals. This means that your settings will only be effective until the ECU fully resets. After that, the car will perform as it did before. The S-AFC is only good for last minute at the track tuning. If you want real power though, you'll need a reprogrammed ECU. For a while I used my S-AFC as a monitoring device. For the money it cost to buy one new, though, you're better off just buying some nice guages.

Phatmitzu

iTrader: (34)

Im using A'pexi S-AFC on my Eclipse Turbo. Had it tuned by an local speed shop. Totally got rid of fuel cut with my stock injectors. Gaines total of 7whp at 3000-4000rpm. I say its worth the money. Its about $300 now. But without proper dyno tuning, playing it around by yourself wont do you much good.

Monkey Man

The software is available now, we sell it.

-Jeremy

iboost

For reference, my previous car was a '95 Celica turbo. It was running very, very lean so a local tuner shop recommended a Vortec FMU and an Apex'i S-AFC v2.

On my baseline dyno run (running lean, before product were installed), I had 201.4 WHP / 225 ft-lbs TQ. After some tuning and 8 pulls later (plus a very hot engine), my numbers were 228.1 WHP / 250.8 ft-lbs TQ. Now, this is a turbo engine that was running very lean. I don't think you will see this much of a gain w/ a NA engine, but I just post this here so you can have one man's experience as a reference point from which to judge.

For me, the Apex'i S-AFC is rather easy to tune and did the job well. I don't have any direct experience with any of the others you mentioned, so I cannot comment there.

The Apex'i unit, along w/ the FMU made a world of difference and now my Celica pulls a lot harder as its not starving for fuel. Yipeee!

Regards,

iboost

articfury

iBoost, phat, Jeremy, thank you for your responses.

Jeremy, is the e-manage/e-01 combo what GReddy is using on their 350Z TT test car?

race-

I hope you are not referring to me in your allusions. I have never questioned your knowledge, or the validity of your statements. I simply pointed out that this thread was about opinions regarding these units, and not how useful they would be on an assumed setup.

I don't seem to remember asking which of these will give me 40hp. Nor did I say they will give 5hp. I was simply interested in the products for future plans. Therefore, I am doing my own research. As part of that, I was interested in seeing what experiences the community of users here has had with these types of devices.

Man, I remember when this board was about answering questions and not about attacking people.

JD

PS

You may want to read up on the GReddy e-manage. It does allow, through an optional PC kit, for 16x16 Air Flow adjustment. It will also allow for 16x16 timing adjustment with an optional adapter. This is still fine tuning, but it is closer to full EMS than previously available in this price point.

I have also heard good things about the HKS V-Con, but am still researching it.

Monkey Man

Yes.

-Jeremy

ITR#203

Racetested,
What you do not seem to understand is that EVERY CAR IS DIFFERENT. Just cause it does not achieve gains on one car doesnt mean that it wont on another. 11.7 is NOT perfect for a car. Perhaps for a forced induction car, this is acceptable but certainly not a naturally aspirated car. If you look back, I said 13.5-14.0 is good for the street but that 14.7 is THEORETICALLY the best air-fuel mixture. Please read before you criticize. Also, if you would like an example of how a stock car gets gains off a V-AFC (S-AFC but with VTEC control) check the S2000 boards.

AND PLEASE EXPLAIN TO ME HOW BOLT ONS WOULD INCREASE THE GAINS FOR AN AIR FUEL CONTROLLER WHEN STOCK CARS RUN TOO RICH???? Part of the gain from boltons comes from the fact that they improve the air fuel ratio.

The limitations of a S-AFC are seen in that they cannot really ADD fuel. They can trick the computer into putting less fuel in but not more. Also, messing with low throttle settings is a waste of time as OBD II and up cars will reset these according to the what the O2 sensor reads; however, at WOT settings, the ECU goes to a set program with no regard to the O2 sensor so it works just fine.