Power FC NEED your opnion here! Power FC vs AEM vs other mngmt
09-29-09, 08:15 PM
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NEED your opnion here! Power FC vs AEM vs other mngmt
Ok, so I have the PFC in my FD and so far I am pleased with it. I think bang for the buck the PFC has been awesome and it solved a lot of my problems. I have not done any tuning with it yet, I will need to even though it has a safe base tune from the RX7Store (cuz of different elevation, mods etc.), but I'm not looking for a drag car, just a good all around fast car.
One of the main reasons I even bought the PFC is based on this forum. The majority of engine management threads seems to favor the PFC. So I wanted to to have an EMS that there would be plenty of feedback, experience, and potentially better answers if I encountered a problem with the PFC. (PFC: 4,448 threads - AEM: 173 threads. As of this writing.)
The reason for saying all this: is some buddy's of mine (who own a shop and mostly have built DSM's and Honda's) have non-stop dogged on the PFC. They have always tried to get me to buy into the AEM. Even though I have bought the PFC they still talk crap on it, saying that its really hard to work with, its not user friendly, you're going to regret that you bought the PFC and that it is definitely not as good as the AEM. IMO they seemed to have had nothing but difficulty with the AEM and really haven't won any races with it.
SO...What does the critical world of RX7Club say to this? Be honest and blunt. Even the smallest feedback would be appreciated. Do you think I have made an overall right decision? Does the PFC have big potential? Or should I have gone with the AEM?
Thanks all, looking forward to your feedback!
One of the main reasons I even bought the PFC is based on this forum. The majority of engine management threads seems to favor the PFC. So I wanted to to have an EMS that there would be plenty of feedback, experience, and potentially better answers if I encountered a problem with the PFC. (PFC: 4,448 threads - AEM: 173 threads. As of this writing.)
The reason for saying all this: is some buddy's of mine (who own a shop and mostly have built DSM's and Honda's) have non-stop dogged on the PFC. They have always tried to get me to buy into the AEM. Even though I have bought the PFC they still talk crap on it, saying that its really hard to work with, its not user friendly, you're going to regret that you bought the PFC and that it is definitely not as good as the AEM. IMO they seemed to have had nothing but difficulty with the AEM and really haven't won any races with it.
SO...What does the critical world of RX7Club say to this? Be honest and blunt. Even the smallest feedback would be appreciated. Do you think I have made an overall right decision? Does the PFC have big potential? Or should I have gone with the AEM?
Thanks all, looking forward to your feedback!
09-30-09, 05:58 AM
#4
We have customers making 600+ HP with the PFC. It is a great unit that can make plenty of power.
The AEM has a lot more things that can be adjusted, however up until recently it was twice the price of the PFC and really has no support. There are people making lots of power with this ECU also, just a lot fewer of them.
Do not allow your Honda Buddy to dictate what EMS you should be using ing your RX7.
The AEM has a lot more things that can be adjusted, however up until recently it was twice the price of the PFC and really has no support. There are people making lots of power with this ECU also, just a lot fewer of them.
Do not allow your Honda Buddy to dictate what EMS you should be using ing your RX7.
09-30-09, 02:01 PM
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^Thanks for the response! 
Yeah, 600HP is nothing to sniff at, even considering how light the FD's weigh.
"Support" was the word I was looking for. The PFC definitely has more when it comes to the RX7. I'm sure the AEM is great. The price of the AEM was in the deciding factor of what EMS to buy and I have heard, a lot, that there are more things to adjust on it, but for someone like me who doesn't want to be tuning his car every weekend that's fine with me.
Yeah, 600HP is nothing to sniff at, even considering how light the FD's weigh. "Support" was the word I was looking for. The PFC definitely has more when it comes to the RX7. I'm sure the AEM is great. The price of the AEM was in the deciding factor of what EMS to buy and I have heard, a lot, that there are more things to adjust on it, but for someone like me who doesn't want to be tuning his car every weekend that's fine with me.
10-01-09, 12:29 AM
#6
I self tuned my PFC, last dyno on my old setup was 386rwhp.
Here are some limitations:
1. lack of easily controllable switched outputs. That means nitrous or alcohol injection will have to be done with a separate controller if you choose to use them.
2. lack of built-in two step. If you care about drag racing this may bother you
3. lack of precise control of the ISC valve behavior and the self-adjusting idle ignition timing feature. if you aren't even running an ISC this won't matter.
4. no knock retard, limited/useless closed loop control. But Rx-7 knock sensors can be noisy so knock control would be a bit tricky. And a lot of people don't set up closed loop at all anyway.
5. tuning idle AFR with larger primaries can be tricky. there are some workarounds necessary sometimes (injector lag correction)
6. lack of updates and relatively poor support from the manufacturer
Here are some benefits
1. as you've noticed, a lot of information is available for using it on the Rx-7. This is a huge advantage. There are tons of basemaps etc floating around compared to the EMS.
2. user friendly is in the eye of the beholder. There are a lot of menus in the AEM EMS software that you will probably never use, and finding the stuff you want has a significant learning curve. The tabbed layout of the PFC is quicker to navigate than the complex and layered menus of the AEM EMS in my opinion.
3. the PFC does not have any major problems with electrical noise (especially on the crank angle sensor signals) as compared to many other computers out there.
4. injector staging is comparatively very simple to set up in the PFC and is based on duty cycle as opposed to rpm/boost. There are "rules of thumb" settings that people use which don't normally cause lean or rich spots when the secondary's come online. The AEM stages injectors in a different way (injector difference map) that likely will take longer to tune.
5. if you're good with it, the Commander is a useful tool despite its dated 90s look. It has a built-in peak/hold function for air temps, rpm, peak boost, etc. Normally you would have to pay for expensive external gauges to get this. You can make little changes without having to bust out a laptop all the time
6. the PFC can still control fuel, timing, boost, and the cooling fans. The AEM's boost control is much more adjustable but also has a steeper learning curve.
7. sequential turbo control is a lot simpler on the PFC, it's just a check box and some transition settings.
Here are some limitations:
1. lack of easily controllable switched outputs. That means nitrous or alcohol injection will have to be done with a separate controller if you choose to use them.
2. lack of built-in two step. If you care about drag racing this may bother you
3. lack of precise control of the ISC valve behavior and the self-adjusting idle ignition timing feature. if you aren't even running an ISC this won't matter.
4. no knock retard, limited/useless closed loop control. But Rx-7 knock sensors can be noisy so knock control would be a bit tricky. And a lot of people don't set up closed loop at all anyway.
5. tuning idle AFR with larger primaries can be tricky. there are some workarounds necessary sometimes (injector lag correction)
6. lack of updates and relatively poor support from the manufacturer
Here are some benefits
1. as you've noticed, a lot of information is available for using it on the Rx-7. This is a huge advantage. There are tons of basemaps etc floating around compared to the EMS.
2. user friendly is in the eye of the beholder. There are a lot of menus in the AEM EMS software that you will probably never use, and finding the stuff you want has a significant learning curve. The tabbed layout of the PFC is quicker to navigate than the complex and layered menus of the AEM EMS in my opinion.
3. the PFC does not have any major problems with electrical noise (especially on the crank angle sensor signals) as compared to many other computers out there.
4. injector staging is comparatively very simple to set up in the PFC and is based on duty cycle as opposed to rpm/boost. There are "rules of thumb" settings that people use which don't normally cause lean or rich spots when the secondary's come online. The AEM stages injectors in a different way (injector difference map) that likely will take longer to tune.
5. if you're good with it, the Commander is a useful tool despite its dated 90s look. It has a built-in peak/hold function for air temps, rpm, peak boost, etc. Normally you would have to pay for expensive external gauges to get this. You can make little changes without having to bust out a laptop all the time
6. the PFC can still control fuel, timing, boost, and the cooling fans. The AEM's boost control is much more adjustable but also has a steeper learning curve.
7. sequential turbo control is a lot simpler on the PFC, it's just a check box and some transition settings.
10-01-09, 11:22 PM
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^ Wow! Nice run down of pros and cons. Some of those things I never knew about the PFC and AEM.
There is still a learning curve for me with the PFC and trying to understand how it all works, but I am a "get in there and do it yourself" kind of person...that's how I learn and I want to know how/why things work.
There is still a learning curve for me with the PFC and trying to understand how it all works, but I am a "get in there and do it yourself" kind of person...that's how I learn and I want to know how/why things work.
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10-02-09, 12:06 AM
#8
go to the AEM website and download the AEMpro software, there should be a link in the forums. try to locate the main fuel and ignition maps, the idle stuff, the injector staging stuff, the switched outputs. read through the lengthy and detailed help file.
You need to make your own decision, there are tradeoffs.
One of the things I really like about the AEM EMS is how precisely you can control the ISC. There is an actual map of ISC valve duty cycle, and specific parameters to control how the ISC valve kicks in under deceleration and how sensitive the self-adjusting system is.
here is a screenshot of some of the major tables you would be using in the EMS:
In the upper left is the fuel map. That's like viewing the datalogit in the base map tab with INJ x base selected. The ignition basemap is way different from what you would normally see on an FD, it runs hardly any timing advance at all. The ignition difference map is the split map. I don't like the split map that AEM includes by default, 8 degrees of split is pushing it in terms of safety, but maybe with the super retarded leading timing it works ok. The fuel difference map is your injector staging. I think they have 70% in the high load areas because there are 1680's on this included basemap and 550 is around 30% of 1680 if you divide them. The idle % vs target is the ISC base duty cycle value vs target rpm. Then there are closed loop control parameters (kind of like gain on an EBC) on top of that, same with the idle ignition control settings. There's also a bunch of precise settings for controlling deceleration ISC behavior which I really wish the PFC had.
The boost fuel correction table is kind of like the INJ map in the PFC... people will set the fuel map to a single value across all boost load points, and then scale it % wise in the boost compensation table. The disadvantage is that it doesn't fully take into account changes in engine volumetric efficiency at various boost levels. You can use a similar strategy in the PFC if you wanted to by using the recalc function, setting all boost area injector pulsewidth values the same, and tuning with the INJ map.
You need to make your own decision, there are tradeoffs.
One of the things I really like about the AEM EMS is how precisely you can control the ISC. There is an actual map of ISC valve duty cycle, and specific parameters to control how the ISC valve kicks in under deceleration and how sensitive the self-adjusting system is.
here is a screenshot of some of the major tables you would be using in the EMS:
In the upper left is the fuel map. That's like viewing the datalogit in the base map tab with INJ x base selected. The ignition basemap is way different from what you would normally see on an FD, it runs hardly any timing advance at all. The ignition difference map is the split map. I don't like the split map that AEM includes by default, 8 degrees of split is pushing it in terms of safety, but maybe with the super retarded leading timing it works ok. The fuel difference map is your injector staging. I think they have 70% in the high load areas because there are 1680's on this included basemap and 550 is around 30% of 1680 if you divide them. The idle % vs target is the ISC base duty cycle value vs target rpm. Then there are closed loop control parameters (kind of like gain on an EBC) on top of that, same with the idle ignition control settings. There's also a bunch of precise settings for controlling deceleration ISC behavior which I really wish the PFC had.
The boost fuel correction table is kind of like the INJ map in the PFC... people will set the fuel map to a single value across all boost load points, and then scale it % wise in the boost compensation table. The disadvantage is that it doesn't fully take into account changes in engine volumetric efficiency at various boost levels. You can use a similar strategy in the PFC if you wanted to by using the recalc function, setting all boost area injector pulsewidth values the same, and tuning with the INJ map.
10-02-09, 12:42 AM
#9
Also, the boost control feature is way more precise than the PFC or any external boost controller but you will have a steeper learning curve. The PFC has you set a basic duty level and a basic target boost, and then you just fiddle with it until boost is good enough. The PFC sets the gain settings for you, which has its advantages and disadvantages.
The AEM is much more precise:
First, there is a duty map. This is a lot like an AVC-R or to a much lesser extent the AEM tru-boost EBC (which has no closed loop). Then there are boost target tables for use with closed loop feedback, and you can scale down the boost targets for various conditions in other maps not pictured here. The main closed loop method uses a normal PID (Proportional, Integral, Derivative) strategy, wikipedia PID control if you don't know much about it. It is the exact control strategy used in the OEM Subaru STi etc boost controller built into the ECU. There is some discussion in the Haltech forum about how to set up that type of control.
If you don't want to run an ISC valve, you run straight pump gas, you want to run an external boost controller, you don't need/care about precisely controlling closed loop idle ignition... I just don't see how you would make use of the EMS. It gives you control, but if you don't want to use that additional control for whatever reason, why bother? That's what bothers me about debates over which standalone is "better." To a certain extent it's like asking which turbo is "better." Dropping a more expensive computer in with more features isn't going to make your car drive better or make more power. Even if you pay a knowledgable tuner to set this stuff up, unless you pay them a ton of money they won't have time to get it fully optimized for your engine.
The AEM is much more precise:
First, there is a duty map. This is a lot like an AVC-R or to a much lesser extent the AEM tru-boost EBC (which has no closed loop). Then there are boost target tables for use with closed loop feedback, and you can scale down the boost targets for various conditions in other maps not pictured here. The main closed loop method uses a normal PID (Proportional, Integral, Derivative) strategy, wikipedia PID control if you don't know much about it. It is the exact control strategy used in the OEM Subaru STi etc boost controller built into the ECU. There is some discussion in the Haltech forum about how to set up that type of control.
If you don't want to run an ISC valve, you run straight pump gas, you want to run an external boost controller, you don't need/care about precisely controlling closed loop idle ignition... I just don't see how you would make use of the EMS. It gives you control, but if you don't want to use that additional control for whatever reason, why bother? That's what bothers me about debates over which standalone is "better." To a certain extent it's like asking which turbo is "better." Dropping a more expensive computer in with more features isn't going to make your car drive better or make more power. Even if you pay a knowledgable tuner to set this stuff up, unless you pay them a ton of money they won't have time to get it fully optimized for your engine.
10-03-09, 02:06 AM
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^Thanks a lot for all the great info! I am not running an ISC (I'm not sure if that was a good decision or not 
) I am not really trying to get this down to complete precision, but to have a computer than can be tuned, add good power and have an overall decently fast car. I think for the all out drag racer and autocross racer the precision would have a greater benefit. Like you said, if that is what you wanted you would be spending a lot of your own time or paying someone constantly to always tune/adjust your settings.
Do you own your own race car shop? Seems like you have quite a bit of experience with the different engine managements.
) I am not really trying to get this down to complete precision, but to have a computer than can be tuned, add good power and have an overall decently fast car. I think for the all out drag racer and autocross racer the precision would have a greater benefit. Like you said, if that is what you wanted you would be spending a lot of your own time or paying someone constantly to always tune/adjust your settings.Do you own your own race car shop? Seems like you have quite a bit of experience with the different engine managements.
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