I've been searching around, and found that half of the EVO owners are running super rich (even us 91 octane guys) with the full intake/exhaust bolt on packages. And then I see some guys that are running lean I suppose, because they have fuel pumps and injectors.

My car right now is leaned out 12% at 7000rpm, so I can't imagine having to add a fuel pump or injectors.

Here are my mods and my AFC settings:

B&B 3" DP
Perrin 3" TP with o2 simm
Helix 3" Catback
Weapon-R 2G Eclipse air fiter
Buschur Upper I/c Pipe with HKS BOV
SAFC
Hallman boost controller @ 1.4 bar (20-21psi)

My afc settings:

1600 (0)
2200 (0)
2800 (-1)
3400 (+2)
4000 (+2)
4600 (+1)
5200 (-3)
5800 (-7)
6400 (-10)
7000 (-12)
7600 (-12)

MY EGTs at top of 3rd are 780C.

I have an AEM Uego, but don't have a o2 bung in my downpipe yet to tune, so it's just a butt-o-meter tune.

But the car definately pulls better the more I lean it out.

I have a Buschur FMIC on the way, and I'm wondering if I will need a fuel pump (I have a supra pump laying around). I just don't see that I will need a fuel pump... maybe richen it up? I know every car is different, but is my car really this pig rich?

Maybe I just need to get my car tuned correctly

Any thoughts?

 

Your partially right about "too much fuel" and the question of upgraded fuel injectors or pump.. But let me put it this way..

If you stand on a branch, and the branch is known to support 150 pounds, you currently weigh 130, the branch won't break.. but if you jump UP AND DOWN on the branch, there's a chance it could break..

Fuel pump and fuel injector upgrades are intended to provide a margin of capacity that just isn't there when you begin to upgrade other aspects of your car..

The main side effect of bigger injectors is in turn by leaning out the ECU to compensate (scale) for the injectors, you've effectively raised the point where fuel cut would kick in (More or less, there's a little more to it than just that.. but its essentially true)

the higher volume fuel pump even with stock injectors will prevent the fuel system from starving from fuel when volume is needed, remember, the pump doesn't really increase the pressure all that much, but allows more consistent fuel volume without the pressure drop. Its more essential under sustained load where the stock pump could overheat or fail when trying to keep pushing the fuel required..

The car runs rich stock, there's no question about it.. However as you begin adding horsepower, your fuel requirements also begin to grow.. initially with very few mods, the system can handle it (MBC, S-AFC, Exhaust) but at some point, your going to begin to be able to get more air into the engine (higher boost, better intercooler pipe routing, more efficient intercooler, etc) that is when the fuel requirements begin to exceed what the stock components can do.

Its not a requirement to make those upgrades, but they are for a margin of safety and allow you to tune the car for whatever conditions without exceeding the capabilities of the components.

 

the thing is you honestly have no idea how rich or lean your car is runing by solely looking at EGT's...

get the UEGO in there and then do some dataloging, looking at timing and fuel trims

 

Nice Nice Nice! Very well put.
You always help out guys! I am starting to become a big fan of yours!

 

Hey bOoost your setting is very close to mine. I also found that if I lean it out more the car feels more powerful. But at the same time the engine sounds more harsh. You can definitely hear more engine noise at the same rpm. So I left the setting as it is just to be on the safe side, here it is,

2400 +1
2900 +2
3500 +2
4000 +2
5000 -1
5400 -3
5800 -5
6200 -7
6800 -8
7000 -8

My egt never exceeds 1250 F at the downpipe. I know I am definitely not lean anywhere in the rpm range. But I do feel like I want to work the midrange a little bit cause it feels dog slow after adding those fuel whereas before at 0 correction it hauled ***. Does that mean I want to go back to 0 at midrange instead of positive settings. Some people said it can go lean in the midrange with the intake so I just added some fuel. Anybody care to comment or discuss. I am all ears.
MalibuJack can you give me a advise on the setting I know you are the expert. My mods are Biltz SUS intake, AMS MBC (19psi), HKS Super AFR, Boost and EGT gauge, Removed muffler valve, modified stock downpipe.