Adjusting AFRs for emission removal..?

[Bigsyke]

Ive removed all my emissions on my OBD1 S14;

KS
EGRBPT
EVAP

Ive used the resistors to cover the CELs and keep the ECM happy. However with the lack of the EGR system, my understanding is the car will run stupid rich still. Ive compensated for the increased cylinder temps via a Nismo thermo, Mishi Radiator, Honda type II, TB bypass (which also bypasses the IAC), Diesel water wetter, and an upper radiator shroud.

I do have a nismo AFPR, set to OE pressure, however can I possibly compensate for the rich conditions by bumping the PSI down a few pounds? Or would the o2 compensate for this by increasing injector load? What im also trying to prevent is fuel/oil dilution.

Thanks!

PS Im using oxygenated fuel at 91*

[lok]

Do you have a wideband?

[BigVinnie]

Ive used the resistors to cover the CELs and keep the ECM happy. However with the lack of the EGR system, my understanding is the car will run stupid rich still.

Don't know were you got that information from.
Your A/Frs are always based off of theoretical pulse width.
So what ever intake velocity goes in through the MAF will determine your pulse width.
If the EGR use to bring in hot gasses throuh the manifold it still wont change what the MAF reads. Your engine should be getting more air coming into the system with the removal of the EGR.

unless your ecu throws a cell, it would be the only time you would be running pig rich. I would get something like ecu talk so you can figure out what your engine is doing.

[S14_Kouki]

lean your car out when u do your emissions

[Bigsyke]

Don't know were you got that information from.
Your A/Frs are always based off of theoretical pulse width.
So what ever intake velocity goes in through the MAF will determine your pulse width.
If the EGR use to bring in hot gasses throuh the manifold it still wont change what the MAF reads. Your engine should be getting more air coming into the system with the removal of the EGR.

unless your ecu throws a cell, it would be the only time you would be running pig rich. I would get something like ecu talk so you can figure out what your engine is doing.

The burnt gas vapors take up space in the A/F mix, which register on the o2 as neither o2 or fuel. By removing the EGR, the o2 sends more fuel into the mixture. Its in multiple threads for emissions removal and has been confirmed that you will run rich. It has been stated you need to alter the fuel maps to compensate for the lack of unburn/unmeasured gases.

lean your car out when u do your emissions

How so? How do you measure how much your supposed to lean out the mix? I do not have a WBO2, only the Nismo FPR

[BigVinnie]

The burnt gas vapors take up space in the A/F mix, which register on the o2 as neither o2 or fuel. By removing the EGR, the o2 sends more fuel into the mixture. Its in multiple threads for emissions removal and has been confirmed that you will run rich. It has been stated you need to alter the fuel maps to compensate for the lack of unburn/unmeasured gases.


If thats the case why not just use sr20DE injectors? Then you don't have to worry about richness, and you don't need any ecu tuning.
Aren't those injectors 260cc (actually 259cc). that should put you right on the cusp of running ultra lean ka injectors are 270cc.

EDIT: MY BAD didn't know you were talking about turbo charging. Disregard first post

Anyway I still don't know what your talking about because the ecu will want a target A/Fr. Exhaust gas takes up space (manifold pressure) reducing the velocity at the MAF. In the place of exhaust gas would be more denser air, since the purpose of hot exhaust gas is to expand and heat up air molecules. Technically there should be more air making combustion leaner.The O2 sensor reads the mixture for the ecu. But then again what the fuck do I know (probably nothing).

Correction: it shouldn't make it any more leaner, or any more richer. It just allows more nitric oxide to bond with hydro carbons, making a less complete burn off. EGR's purpose is to ruduce NOX emissions by warming up the air and reducing cylinder temperature by using less air in the cylinder. Making teh nitric oxide less of a compound to attach too HC and other polluting chains.