things are getting interesting.
#1
things are getting interesting.
hopefully this turns out better than the last attempt from someone else.
http://www.lexusf.com/forums/showthread.php?t=1972
http://www.lexusf.com/forums/showthread.php?t=1972
#7
Yeah, next friday I think were going to hit towers. Janoy might have an S5 with a new ISS exhaust up there and one of the local IS-F owners wants to hear my exhaust. So you should come so he can hear yours too since you have the track and I have the street. And I want to hear about this diffuser I think you said you were workig on, cuz I got a few ideas I want to run by someone.
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#9
Sorry if I'm missing something here, but how do they figure to retune the ECU? Isn't that a necessary step to handling the additional hp and adjust the fuel mapping?
I don't really understand the technical side of these mods, so if someone could shed some light it would be appreciated.
All I keep seeing is a re-run of the previous MHP debacle.
I don't really understand the technical side of these mods, so if someone could shed some light it would be appreciated.
All I keep seeing is a re-run of the previous MHP debacle.
#10
They are using the AEM FI/C 8. It and they have modded it to work on the IS-F. Then they can control the fuel maps, ignition maps, and some other things. Its really a good step for the community. If you look at their (elite) threads at LexusF you will see what i am talking about.
#13
They are using the AEM FI/C 8. It and they have modded it to work on the IS-F. Then they can control the fuel maps, ignition maps, and some other things. Its really a good step for the community. If you look at their (elite) threads at LexusF you will see what i am talking about.
#14
No, they can't control the maps. They can rearrange them, but they're not changing the maps themselves. Piggybacks can only fool the ECM into thinking something else is going on by altering the signals the ECM uses to determine what the engine's operating parameters are. It's the same way everyone started tuning Supras a long time ago - HKS VPC with an SAFC or some other fuel controller and you'd get started tweaking. The fundamental problem was, the maps were fixed, so you'd just tell the ECM a lie and it would look somewhere else in the table for the answer. It's not a good long term solution and never has been.
#15
This is from Andy at Elite,
How the FIC works.
I don't mean to word in a way that sounds like I am talking to children. I know there are a few of you out here that do not know much about cars and I want to make sure I cover the basics. So here it goes!
Ok the AEM FIC was designed because there was never really a good piggyback tuning option that could control ignition timing and fuel on the newer cars with out throwing check engine lights and or putting the car in limp mode. The difference between a piggyback and standalone is pretty much in the name. A piggyback uses the stock ECU and a standalone does it all on its own. The thing that makes the AEM FIC stand out over other piggy back systems is that most of the other ones change sensor INPUTS to the stock computer ONLY. For example, they would take the Mass Air Flow sensor voltage and change it to make the computer think there is more or less air going into the motor when there really is not. What this does is it makes the computer run a different section of its map, and that could add or subtract fuel, timing, camshaft timing, etc.
The AEM is different in the sense that it can modify some Inputs and some Outputs. The FIC hooks up to the Cam and Crank sensor and uses their signals to get its RPM signal and the FIC can actually modify them at the same time to adjust ignition timing. Now it does this by delaying the cam and crank signal to the stock ECU which at the spark plug delays when it fires. Now this is where we run into the issue on the Stock NA IS F. We can not ADD ignition timing we can only remove it. So I don't know if we would see many gains on a completely stock car. I would love to get a car here for a turbo install and put the FIC on first to see what it would do for an NA car.
Now for the fueling, the FIC modifies the signal from the stock ECU to the injectors so the stock computer really never knows what the injectors are actually doing. So as long as the O2 sensors are reading what they should from the factory there should be no adaptation made from the stock ECU, and that is what we have seen thus far. The issue we ran into is that the FIC can only double the injector pulse, but it can remove it as much as we want. This is the reason that we are installing larger injectors in the car we have now. There is a fine line though, if we go too large with the injectors then we loose resolution during idle and part throttle and we may end up a bit rich. So that is what I am currently working on getting all figured out.
There are also many other features of the FIC. It has an O2 feed back option which allows us to wire in a AEM UEGO Wideband and the FIC can adjust fueling to the settings that you input, kind of a "closed loop" but it can only do it to a specified percent. You never want a computer to rely just one sensor for its fuel trims in case that sensor fails. It has a built in boost control function, and also a switched input and output. So it could control Nitrous, Methonal, or something else of your choice.
How the FIC works.
I don't mean to word in a way that sounds like I am talking to children. I know there are a few of you out here that do not know much about cars and I want to make sure I cover the basics. So here it goes!
Ok the AEM FIC was designed because there was never really a good piggyback tuning option that could control ignition timing and fuel on the newer cars with out throwing check engine lights and or putting the car in limp mode. The difference between a piggyback and standalone is pretty much in the name. A piggyback uses the stock ECU and a standalone does it all on its own. The thing that makes the AEM FIC stand out over other piggy back systems is that most of the other ones change sensor INPUTS to the stock computer ONLY. For example, they would take the Mass Air Flow sensor voltage and change it to make the computer think there is more or less air going into the motor when there really is not. What this does is it makes the computer run a different section of its map, and that could add or subtract fuel, timing, camshaft timing, etc.
The AEM is different in the sense that it can modify some Inputs and some Outputs. The FIC hooks up to the Cam and Crank sensor and uses their signals to get its RPM signal and the FIC can actually modify them at the same time to adjust ignition timing. Now it does this by delaying the cam and crank signal to the stock ECU which at the spark plug delays when it fires. Now this is where we run into the issue on the Stock NA IS F. We can not ADD ignition timing we can only remove it. So I don't know if we would see many gains on a completely stock car. I would love to get a car here for a turbo install and put the FIC on first to see what it would do for an NA car.
Now for the fueling, the FIC modifies the signal from the stock ECU to the injectors so the stock computer really never knows what the injectors are actually doing. So as long as the O2 sensors are reading what they should from the factory there should be no adaptation made from the stock ECU, and that is what we have seen thus far. The issue we ran into is that the FIC can only double the injector pulse, but it can remove it as much as we want. This is the reason that we are installing larger injectors in the car we have now. There is a fine line though, if we go too large with the injectors then we loose resolution during idle and part throttle and we may end up a bit rich. So that is what I am currently working on getting all figured out.
There are also many other features of the FIC. It has an O2 feed back option which allows us to wire in a AEM UEGO Wideband and the FIC can adjust fueling to the settings that you input, kind of a "closed loop" but it can only do it to a specified percent. You never want a computer to rely just one sensor for its fuel trims in case that sensor fails. It has a built in boost control function, and also a switched input and output. So it could control Nitrous, Methonal, or something else of your choice.