Installing Apexi SAFC II
09-14-09, 12:54 PM
#1
Installing Apexi SAFC II
Hi everyone, I got an Apexi SAFC II from a fellow Rx-7 Club member during the 7 Stock North meeting recently, and would like to install it. What are the things need to aware when tuning it? Are there different types of tuning or what? Please lecture me.
Thanks
Thanks
09-14-09, 01:23 PM
#2
Sell it and get a PowerFC unless you want to blow your motor (maybe not blow it, but a piggyback fuel only computer is not what you want). Usually this is only used on 2nd gens that want to run a little more boost with the stock computer (that I heard of).
thewird
thewird
09-14-09, 03:37 PM
#4
The installation isn't the problem. You just pull the wiring diagram and any half skilled mechanic (or anyone with common sense and some motivation) can splice it in.
It's the fact that it isn't very useful to begin with. I took some time to read the manual just now to find out how its controlled. All it does is correct by a given % by RPM. There is no function to correct by boost level, only by TPS which is fine for an N/A but not for a turbo car. You can't control timing, or adjust by temperature, or many other things that are important in tuning. Even if this thing is tuned "correctly", its just a matter of time before your engine goes boom when the weather changes and conditions aren't ideal or even if you give it a WOT in a specific way that it doesn't add the correct amount of fuel. Let's say your on an steep uphill, the twins can generate boost with barely any throttle, the unit doesn't add enough fuel, BOOM and then you go "but I wasn't even pushing it" and then you have to dish out 4k+ for an engine job and buy the correct computer that you should have in the first place.
This is useless and possibly even dangerous to put in a 3rd gen in my opinion.
thewird
It's the fact that it isn't very useful to begin with. I took some time to read the manual just now to find out how its controlled. All it does is correct by a given % by RPM. There is no function to correct by boost level, only by TPS which is fine for an N/A but not for a turbo car. You can't control timing, or adjust by temperature, or many other things that are important in tuning. Even if this thing is tuned "correctly", its just a matter of time before your engine goes boom when the weather changes and conditions aren't ideal or even if you give it a WOT in a specific way that it doesn't add the correct amount of fuel. Let's say your on an steep uphill, the twins can generate boost with barely any throttle, the unit doesn't add enough fuel, BOOM and then you go "but I wasn't even pushing it" and then you have to dish out 4k+ for an engine job and buy the correct computer that you should have in the first place.
This is useless and possibly even dangerous to put in a 3rd gen in my opinion.
thewird
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09-14-09, 03:57 PM
#8
Thinking about it now maybe the 2nd gen's that I heard about using it were N/A's and not turbo's. So they just wanted to tweak the fuel a bit or changed injectors and wanted to correct for that. But on a turbo car this thing really doesn't make any sense at all.
thewird
thewird
09-14-09, 09:00 PM
#11
It could work in your RX-8 but keep in mind the RX-8 computer is a little advanced and will try to correct what you are changing. So the end result is the 2 computers will end up fighting each other. Now that I think about it, its probably not a good idea on the RX-8 either :P. It's only really good for N/A cars that don't have advanced closed loop control. In other words, much older cars.
I say sell it to another 2nd or 1st gen owner or try to get the guy that sold it to you to take it back. Maybe eBay too since that broadens the market of potential buyers.
thewird
I say sell it to another 2nd or 1st gen owner or try to get the guy that sold it to you to take it back. Maybe eBay too since that broadens the market of potential buyers.
thewird
09-16-09, 01:03 AM
#18
There is nothing wrong with running this on a turbo car. Perhaps a rotary, but that i wouldn’t know too much about , as i never owned a turbo charged rotary. Its an air to fuel ratio controller, and is ideal if you wish to up your boost, or are running too rich / lean, or like my supra, have a fuel cut, and you have a by pass sytem and the stock ecu does not register the extra air flow, so this helps compensate for it. the safc 2 comes with two maps , and i believe allows you to tune to 8-12 points. It’s a piggyback, so don’t expect too much in the world of tuning, but it is ok for what it does. There is no reason , again may be for a rotary, your engine should go boom if tuned correctly. My boy with his mk4 supra used his safc for 600 hp for well over a year until he switched to a standalone.
I have several friends withmk3 supra with lexus afm 550’s and what not, 240sx with 2jz’s, srd’s with safc’s and all are running fine. Now, a used one , well that is taking a gamble, as it can be faulty or defected, but again, if it is in working , good working that is, condition, it should be fine (AGAIN , lol, i don’t know about turbo rotary applications).
get your stock ecu tuned, if possible, or a standalone (but for 2-300 hp, is it really needed?)
I have several friends withmk3 supra with lexus afm 550’s and what not, 240sx with 2jz’s, srd’s with safc’s and all are running fine. Now, a used one , well that is taking a gamble, as it can be faulty or defected, but again, if it is in working , good working that is, condition, it should be fine (AGAIN , lol, i don’t know about turbo rotary applications).
get your stock ecu tuned, if possible, or a standalone (but for 2-300 hp, is it really needed?)
09-16-09, 02:58 AM
#19
There is nothing wrong with running this on a turbo car. Perhaps a rotary, but that i wouldn’t know too much about , as i never owned a turbo charged rotary. Its an air to fuel ratio controller, and is ideal if you wish to up your boost, or are running too rich / lean, or like my supra, have a fuel cut, and you have a by pass sytem and the stock ecu does not register the extra air flow, so this helps compensate for it. the safc 2 comes with two maps , and i believe allows you to tune to 8-12 points. It’s a piggyback, so don’t expect too much in the world of tuning, but it is ok for what it does. There is no reason , again may be for a rotary, your engine should go boom if tuned correctly. My boy with his mk4 supra used his safc for 600 hp for well over a year until he switched to a standalone.
I have several friends withmk3 supra with lexus afm 550’s and what not, 240sx with 2jz’s, srd’s with safc’s and all are running fine. Now, a used one , well that is taking a gamble, as it can be faulty or defected, but again, if it is in working , good working that is, condition, it should be fine (AGAIN , lol, i don’t know about turbo rotary applications).
get your stock ecu tuned, if possible, or a standalone (but for 2-300 hp, is it really needed?)
I have several friends withmk3 supra with lexus afm 550’s and what not, 240sx with 2jz’s, srd’s with safc’s and all are running fine. Now, a used one , well that is taking a gamble, as it can be faulty or defected, but again, if it is in working , good working that is, condition, it should be fine (AGAIN , lol, i don’t know about turbo rotary applications).
get your stock ecu tuned, if possible, or a standalone (but for 2-300 hp, is it really needed?)
If tuned "correctly" to never blow up, it would only ever run right at WOT and run rich as hell anywhere else. This device WILL NOT work in any turbo vehicle, piston or rotary alike.
The stock computer can't be flashed. The PowerFC is really the only option and is better then going full standalone like a Haltech (aka Helltech) in most cases.
thewird
09-16-09, 08:19 AM
#20
^^^ what are you talking about? I own a a turbo supra ( i sai di neve rowned a rotary TURBO), and IT will work with a turbo car, And you can set it to run on a set amount of points as i said above (i believe 8- 12 , something around there. ), and I have several friends who can attest to this being use don a turbo, PISTON engine cars, Not to mention im in their cars 3-5 times a week, and the fastest one doing high 11’s (not the fastest in the world, but proof that it doe sit job and not cause an engine to go “BOOM” (( its a 240 sx with a 2jz gte in it)) all day every day.
I will be setting my car up lexus afm, 550’s, fpr, 255 pump, LIEK ALL MK3 owners who go this way, and will use a safc to tune the car, AND it will work like a charm.
I don't know where you guys get your information from.
Facts - it will work , is it the best ???? NO it has it's limits, as any piggyback set up does,. Is it better than getting your ecu tuned or running a standalone? Hell no, but i never said it was.
Perhaps i f you have never used it on a turbo car (Pistons, or rotary), you shouldn't be telling people that sit is no good nor will it work. AS IT DOES! You have to know what you are doing, and for something like 2-300 HP it should BE no problem, what so ever
RIght now im helping a firend tune his, at WOT he has 11's and at normal cruising13.7 range, and there are other reissues (not SAFC related), with his car.
The whole point of the safc is to control your air to fuel ratio’s,, again as i mentioned above, for people like me on my supra, who cheat / bypass the afm system and allow more air than registered to the ecu, so now i need something to compensate for the unregistered air, and the safc will help me do that.
I will be setting my car up lexus afm, 550’s, fpr, 255 pump, LIEK ALL MK3 owners who go this way, and will use a safc to tune the car, AND it will work like a charm.
I don't know where you guys get your information from.
Facts - it will work , is it the best ???? NO it has it's limits, as any piggyback set up does,. Is it better than getting your ecu tuned or running a standalone? Hell no, but i never said it was.
Perhaps i f you have never used it on a turbo car (Pistons, or rotary), you shouldn't be telling people that sit is no good nor will it work. AS IT DOES! You have to know what you are doing, and for something like 2-300 HP it should BE no problem, what so ever
RIght now im helping a firend tune his, at WOT he has 11's and at normal cruising13.7 range, and there are other reissues (not SAFC related), with his car.
The whole point of the safc is to control your air to fuel ratio’s,, again as i mentioned above, for people like me on my supra, who cheat / bypass the afm system and allow more air than registered to the ecu, so now i need something to compensate for the unregistered air, and the safc will help me do that.
09-16-09, 11:23 AM
#21
People need to be careful when speaking in absolutes. The SAFC will and does work on turbo cars. Many types of cars are running them with decent success.
With rotaxes, they are more suited to NA applications, since you can tie it into the TPS signal. It has a high and low range, and rpm increments. NA rotax guys generally use them to lean out the mixture, since the stock ECU runs too rich.
The problem with using them on an FD, is that you need to tie into the MAP signal and are manipulating the voltages to the stock ECU, basically tricking it into thinking you are running more or less boost than you actually are, thus chaning the fuel mixture in those areas. Again, this will work if you are running stock boost and just want to lean it out. Problem with the FD is that fuel cut at WOT is very close to stock boost levels, 10.8 psi I think. So, if you try to go richer, you'll just hit fuel cut all the time because the stock ECU thinks you are running more boost.
With rotaxes, they are more suited to NA applications, since you can tie it into the TPS signal. It has a high and low range, and rpm increments. NA rotax guys generally use them to lean out the mixture, since the stock ECU runs too rich.
The problem with using them on an FD, is that you need to tie into the MAP signal and are manipulating the voltages to the stock ECU, basically tricking it into thinking you are running more or less boost than you actually are, thus chaning the fuel mixture in those areas. Again, this will work if you are running stock boost and just want to lean it out. Problem with the FD is that fuel cut at WOT is very close to stock boost levels, 10.8 psi I think. So, if you try to go richer, you'll just hit fuel cut all the time because the stock ECU thinks you are running more boost.
09-16-09, 11:26 AM
#22
Its a fuel computer that can't adjust for load. I'm sure this works amazing at the drag strip since all you ever do is full throttle.
Well if you want to go doing custom mods to make it work for something it wasn't designed to do to begin with. Do you really think that is the correct way to go about something? In the end, its just a hack and you will never be able to make it work perfectly.
thewird
People need to be careful when speaking in absolutes. The SAFC will and does work on turbo cars. Many types of cars are running them with decent success.
With rotaxes, they are more suited to NA applications, since you can tie it into the TPS signal. It has a high and low range, and rpm increments. NA rotax guys generally use them to lean out the mixture, since the stock ECU runs too rich.
The problem with using them on an FD, is that you need to tie into the MAP signal and are manipulating the voltages to the stock ECU, basically tricking it into thinking you are running more or less boost than you actually are, thus chaning the fuel mixture in those areas. Again, this will work if you are running stock boost and just want to lean it out. Problem with the FD is that fuel cut at WOT is very close to stock boost levels, 10.8 psi I think. So, if you try to go richer, you'll just hit fuel cut all the time because the stock ECU thinks you are running more boost.
With rotaxes, they are more suited to NA applications, since you can tie it into the TPS signal. It has a high and low range, and rpm increments. NA rotax guys generally use them to lean out the mixture, since the stock ECU runs too rich.
The problem with using them on an FD, is that you need to tie into the MAP signal and are manipulating the voltages to the stock ECU, basically tricking it into thinking you are running more or less boost than you actually are, thus chaning the fuel mixture in those areas. Again, this will work if you are running stock boost and just want to lean it out. Problem with the FD is that fuel cut at WOT is very close to stock boost levels, 10.8 psi I think. So, if you try to go richer, you'll just hit fuel cut all the time because the stock ECU thinks you are running more boost.
thewird
09-16-09, 12:30 PM
#23
I'm not disputing that a piggyback system is not the correct way to go about things. I merely disputed the generalization you made about the SAFC not working with any turbo application. 
If I where Ka Kui, I'd sell it. Get the AEM if I wanted to keep the stock harness and sequential twins, or Autronic if I wanted an EMS that can do anything.
But, since I'm getting too old and grumpy, I'm all about stock ECU these days.
If I where Ka Kui, I'd sell it. Get the AEM if I wanted to keep the stock harness and sequential twins, or Autronic if I wanted an EMS that can do anything.
But, since I'm getting too old and grumpy, I'm all about stock ECU these days.
09-16-09, 06:51 PM
#24
I'm not disputing that a piggyback system is not the correct way to go about things. I merely disputed the generalization you made about the SAFC not working with any turbo application.
If I where Ka Kui, I'd sell it. Get the AEM if I wanted to keep the stock harness and sequential twins, or Autronic if I wanted an EMS that can do anything.
But, since I'm getting too old and grumpy, I'm all about stock ECU these days.
If I where Ka Kui, I'd sell it. Get the AEM if I wanted to keep the stock harness and sequential twins, or Autronic if I wanted an EMS that can do anything.
But, since I'm getting too old and grumpy, I'm all about stock ECU these days.
Are you forgetting the PowerFC that works 100% like stock without any hacking of anything? Literally plug and play, 10 minutes and your running (on base map untuned).
Stock ECU is nice if your well, stock. lol. And even so, its a lot easier to troubleshoot if your have something like the PowerFC.
note: I still think this device has no place in a turbo vehicle but I guess that would be my opinion now.
thewird