After talking to another member about headers, it was brought to my attention that installing headers could disrupt the fuel\air ratio making the engine run lean. Can anyone elaborate on this issue?

 

i've noticed on 02's headers actually make the car run pig rich (seen this on two or three cars here in socal on the dyno)

but yes, your A/F ratios will definitely change considering how much exhaust restrictions are taken out on the 3.5's

 

looks like its time to consider ecu work... what are my options for correcting the ratio? should i get the TS ecu modification or look into an aftermarket AFC?

 

From what I have read on the .org I wouldnt recommend getting your ecu upgraded until you have completed your mods as they will program it based on what you have on your car.

 

also getting an ECU if you have an auto would just be a waste of money. An AFC would be able to work here right?

 

getting the ecu mod after all other performance additions makes sense. this may be a bit technical, but how does TS know exactly how much to compensate for bolt on parts if my car wont be physically tested there? anyways, its not that important of a question, the results from TS owners have been mostly positive. so then, back to the main issue at hand... TS ecu or AFC?

 

The problem with TS is you have to make one generic program for a wide variety of vehicles (no two maximas run the same). Also they had problems with the auto headers version

I'd opt for the L-spec version for the advanced timing and increased rev limiter and tune with s-afcII to the exact specifications you'd like

 

I have no idea what is ideal for a 5th gen Maxima, but I know that a lot of the B15 SE-R guys are using the Apexi SAFC to help tune their cars.

 

maybe this thread should be in the All Motor forum.

 

ideal as in the A/F ratio that you would like to obtain. TS usually tunes on the rich side as a liability factor

 

I should be receiving my HS headers this week. I plan to install them 1st, and get an S-AFC II down the road. From what I understand, the car will run LEAN before tuning, but not at unsafe levels.

 

nice. mine just arrived. booyakasha!

 

I'm actually running quite rich with the HS headers.

 

there were quite a few 350's that i remember running lean after headers but im sure their 3.5 ecu is very different.

 

rich or lean regardless, the air\fuel mixture will have to be tuned.

 

It's call e-manage.

http://www.greddy.com/

 

I don't want to open a can of worms here, but I've seen some people recommend the Greddy E-Manage and some recommend the Apexi SAFC. Major functional differences? The manufacturer sites seem to indicate that the two devices do a lot of the same things.

 

The subject has been heavily discuss in the past, I believe e-manage has more options, I cc the infos from both website:

e-Manage is an inexpensive programmable fuel management system that allows you to properly tune your factory fuel system without having to change the entire factory ECU system to an expensive "stand-alone" unit. The e-Manage system is a universal "piggy-back" type unit which taps into most Japanese factory ECU wiring, by utilizing the existing sensors. * Basic functions will allow the user to slightly alter factory injector duty-cycle (± 20% at 5 preset RPM points) by intercepting and altering airflow or MAP sensor signals. For Honda VTEC cars you can adjust the VTEC shift point. Additional features are built into the system but are only accessible through the use of the e0-1 programmer or our PC-Windows based "e-Manage Support Tool" communication software (Please see our Authorized GReddy Support Dealers for more information). * There is a 16x16 airflow adjustment map, larger main injector correction adjustment, upgrade air flow meter adjustment, boost limiter cut, anti-engine stall, VTEC-fuel adjustment, real-time map trace, real-time display, real-time communication and basic Data-logging. * With the use of our "Optional Injector Harness" and the software, the unit has the ability to control an additional 16x16 injector duty cycle map and the controls for adding up to 2 additional sub-injectors. If the "Optional Ignition Harness" and the software are used the unit has the ability to control a 16x16 ignition timing map. All of the above maps can also be map-traced in real-time as well. If the factory range of map or airflow meter is surpassed, you can incorporate our "Optional GReddy Pressure Sensor and Pressure Harness" to set larger scales of adjustment. All installation and tuning should only be made by a trained technician with proper air/fuel monitoring tools. (Some functions may not be compatible with some applications.)
Price: 815$ with every option for 6 cylindres



APEXi Super AFC II for All Make/Year
Description:*APEXi Super AFC II (Digital) for All Make/Year (401-A907) The second-generation S-AFC is a fuel computer that adjusts fuel/air ratio by modifying the air-flow meter/MAP sensor signal. The S-AFC features a user-definable, eight-point, adjustable fuel curve that can be set in 500 RPM increments. The range of fuel adjustment is +/- 50% at each of the user-defined setting points. On hot-wire vehicles, the Deceleration Air Flow Correction function is capable of curing the erratic idle and stall problems associated with open-atmosphere blow-off valves on hot-wire air-flow meter systems. The S-AFC is capable of monitoring and replaying the following data channels in Numerical, Analog Meter and Graph displays: Intake Manifold Vacuum/Boost Pressure, Air Flow Capacity, Intake Manifold Pressure, Karmann Frequency, Engine RPM, Throttle Position, and Air Flow Correction %.
Price:* $359.95