Okay, let's see who can help me out here. After all my reading, I'm still not entirely certain.

For stage 2, I've upgraded my injectors to 440 c.c. Obviously these are going to put out a ton more fuel than our stock ones of 240 c.c. I've got a Walbro 255 pump and a Vortech 12:1 FMU. Even after resetting the stock ECU to try and have it learn the much increased fuel, the car is running super, super rich at idle. Driving around normally the car does well keeping the AFR to 14.7, but at idle, the car often stalls since its so rich. Is the ECU not able to pull enough fuel for these injectors? I do have a piggyback with tuning software, so do I need to tune the car at idle as well?

Any and all comments appreciated and if you feel you must, I have my flame suit ready

 

time for a tune

 

+12345

 

Do you have a wideband? You have to tune at idle and through your powerband, but you got injectors, a fuel pump, a piggyback, and an FMU? THANK YOU FOR DOING IT THE RIGHT WAY!

 

you cant run 440cc injectors without a tune and expect your idle not to be crap.
First off you definitely dont need an 12:1 ratio fmu with that size injectors... maybe 6:1.
Or if i were you i would just get an aem fpr and an emanage and have some one tune it.

 

Okay - I know I need a tune, hence why I have a

*Wideband
*EGT Gauge
*Piggyback with tuning software

However, my question is more if my fuel system is now overkill for running 9 PSI. Sounds like it maybe.

 

how are your afr's in boost?

 

get rid of the vortech 12:1 and stay w/ 440cc and some AFC and get a FPR.

 

^^ That seems to be a common suggestion. Okay, so I'll ditch the FMU and get an FPR like the AEM.

 

I haven't boosted yet - been too scared But I am going to try it this afternoon and see if I'm leaning out. I know I want to be at about 11 AFR for full bost (9 PSI).

 

yeah same thing is happening to me, but i dont know why. my car is running too too rich, and at idle and driving off the line my car sputters and stuff. only im still in a mess right now.

 

Okay - I've finally got a decent map I think. Just out of curiousity, if you increase your injector size by say 25%, can you decrease all the cell values in your fuel map by 25%? I would think that if your injectors spray 25% more fuel each cycle, then you want to take out that much fuel and your tune should stay the same but just be "shifted", right?

 

That may be a good start.. but i dont believe the adjustments will be that linear across your map. Since the emanage fuel map is based of % adjustments to the ecu's fuel maps, reducing the percentage adjustments by 25% will not result in 25% decrease in fuel to the engine. You will more than likely have to reduce the values by more than 25%.

just as an example if one of the values on your map is 10 that means the emanage will be adding 10% fuel to the ecu's hard coded map. If you were to reduce that value to 5 (50%) , that would not mean you would have 50% less fuel at that point. It would just mean that the emanage is only adding 5% fuel compared to the original 10%.

Having said that I am not entirely sure how the injector correction would factor into this equation.. perhaps boe would have a better idea.

Edit: I forgot your not using an emanage are u.. nm.

 

I am using the RRM Piggyback (Split Second). A value of 10 in the cell means that the piggyback doesn't do anything to the mixture. A value larger than 10, in increments of 0.1 means more fuel is added and a value less than 10 is cutting fuel.