Anyone who has installed this, two questions:

1- where did you pull your ig power from?

2 - what are your current settings?

TIA

 

SCV8 has the AFC unit maybe he'll respond. Also BananaGS has it on the GS forum.... A few guys there have the Apexi S-AFC too...

Good luck,

The Ikon

 

ill let u know what m setting are by the end of next week when i get it back on te dyno to fine tune it,
but i ave some other things done to my car so they might not work the same, but ill post them.
Jc

 

Actually there are instructions that should have came with it when you bought the unit. It has instructions for the Toyota Soarer, but look at the Designation 1UZ-FE where it has engine description, and the wiring diagram whould be listed there. If you dont have that manual, then you can download it from www.apexi-usa.com (click on product documentation). Also be careful when you play with the SAFC as although it does increase power by getting correct mixtures, it is also easy to destroy an engine by running too lean/rich. And dont forget to get it re-checked about 1 week after you get it dyno tuned as the Learning ECU might have compensated for the change in fuel mixtures.


Toan.

 

I think it sucks when I hammer out a good post,then have the software time-out and say thet I'm not registered,so I have to do it all over,oh well.
You can tune the afc yourself,just be careful when doing the hi-rpm,wide open thing,as you can burn up your exhaust valves if you're too lean.
Don't be afraid to go too lean just to find out where you are,just go back again to the rich side until it slows down,then back towards lean again ,if you can without getting into the danger zone.
The engine will run faster towards redline as the mixture leans out,then will get to a point where things slow down,and cut-out(way too lean).As long as you don't hold the throttle down for more than say ten seconds in order to judge to what's going on,you shouldn't destroy anything.
I know that engines will make the same power running a little too rich rather than just right,so by being just bit on the lean side of where the car begins to slow down,you should be safe.

 

I recently put my SAFC on, and tuned it within the past couple weeks. This is on a SC300. What a task!

First off, MAKE SURE you have an AIR/FUEL gauge. If you don't, DO NOT try to tune it!!! You can EASILY KILL you engine fast!! Just get an AIR/FUEL gauge, and run a wire from either of the oxygen sensors thru the grommet in the firewall, and into the gauge.

Factory, you'll see that the ECU keeps the mixture on the lean side of things. While driving, it will bounce back and forth CONSTANTLY. If you just add like 5% fuel over the entire fuel curve, it will automatically re-adjust and you'll lose the extra. Then when you return it to factory settings, the engine runs lean for a while....BAD BAD thing!!

My settings:

Low throttle:
1000rpm 0%
2500rpm 0%
3000rpm 0%
3500rpm 0%
4000rpm 0%
5000rpm 0%
6000rpm 0%
7000rpm 0%

High throttle:
1000rpm 5%
2500rpm 7%
3000rpm 8%
3500rpm 10%
4000rpm 11%
5000rpm 11%
6000rpm 12%
7000rpm 14%

Low throttle point:
97%

High throttle point:
98%

The rest is default.

I do this for my nitrous. THis was, when I'm running nitro, the car gets extra fuel. (even more extra than the Zex kit gives it) Looking at my air/fuel gauge, it was leaning out when running a 125hp shot. So when I made these settings, it is running in the correct ratio, and ALMOST in the rich side. Of course by default, the car will run very rich when you floor it. Any car will.

When I add the supercharger (yes everyone, I have decided to so with a supercharger....actually, I got it already!!!) I will be running the following:

Low throttle:
1000rpm 0%
2500rpm 0%
3000rpm 8%
3500rpm 10%
4000rpm 11%
5000rpm 11%
6000rpm 12%
7000rpm 14%

High throttle:
1000rpm 0%
2500rpm 2%
3000rpm 10%
3500rpm 12%
4000rpm 14%
5000rpm 16%
6000rpm 18%
7000rpm 20%

Low throttle: 50%

High throttle: 99%

This way when I'm at full throttle (on nitro...I keep it ready almost ALL the time) I wil lhavbe PLENTY of fuel! When at less than 50% fuel, the SAFC will not be adjusting anything. ALso at less than 50% throttle, I will likely not be running the RPM's so high that I will require extra fuel for boost. Of course this all depends on what my A/F gauge tells me when I get the supercharger on there! Again, DON'T try to tune this thing without one of those gauges!! I leaned my car out one time, even WITH the A/F gauge, and MAN did it sound bad....ugh.

If you got anymore questions, e-mail me back and I'll try to answer!

SR

 

Thanks for the posts... So the wiring diagram is for the 1JZ, but the 2JZ has same pins on ECU?

Also...I didn't think that any real fuel adjustment was possible when the ECU was in closed loop with the 02 sensor, i.e. low throttle the ECU just ignores the S-AFC settings? I guess that if the 02 sensors were out of the loop completely, the S-AFC has total adjustability over the ECUs built in program for fuel curve?

On my setup, I've disconnected the 02 sensor from the ECU to enable its stock fuel maps program the injector pulses. This ends up running the car much more smoothly in my setup with the turbo... It runs rich, though, and I've just recently done some MAF bypass things to promote more airflow. This leans out the mixture a bit, and still keeps drivability fine. I can run light throttle with the A/F way lean, and still get it rich enough to protect the internals under boost.

Question... Do you think the S-AFC will adjust the stock ECU profile if the 02 sensors are out of the loop? I assume they would as my understanding is that the S-AFC just manipulates the injector pulse duration AFTER it leaves the ECU... Is this correct?

TIA...

 

computer wiz...your running a 125 shot on a single fogger?.....and i guess you deciced you didnt want too much power since your going with a supercharger..just want a little extra kick but not too much...Jeff

 

computer wiz,
i wrote u a looong e-mail to ur PM, but it kicked me off


give me a call and we can talk about it, or e-mail me at my oyther beniceandswallow@yahoo.com

i might have some things u need/want
Jc

 

OK, I've learned that the S-AFC adjusts only the airflow input signal to the ECU. This is gained from the fact that the Air Flow signal is the only wire you actually cut.

According to the technical data I've read so far, the Lexus ECU does monitor the two O2 sensors and also adjusts A/F based upon that data. Soooo, if you have the S-AFC adjusting on the low throttle settings, then fairly quickly the ECU will compensate (like Toan stated). You still will give more HP initially for a second or two though. Hard to ruin anything then, kinda good.

The great thing however is this input is disregarded at WOT, so the high throttle settings will stick and not be compensated for by the O2 feedback.

So, ComputerWiz, what A/F meter did you get and can you perhaps be so kind as to give us some tips on how you use it? I got the AFC properly installed (thanks Toan) and it is reading correctly. WIZ, where did you install? I am going to make a new fiberglass stereo console and install there. WIZ, you the man!!! Running server on a cable modem line, tsk tsk tsk....

 

Once you guys perfect the settings for the SC3 and SC4 please post the EXACT settings you all used. I thought the unit was a peice of cake to install.

Once you have it right, is it fair to say, with the maf adapter, cone filter, and AFC a person will get the same results as a SRT ecu upgrade/intake unit? For a few hundreds less.

From the info I've gotten from Apexi and the Supra forums it is about the same hp gains. Is this true in your opinion? I'm truly lost on this one.

Thomas

 

I'm using an Autometer Sport-Comp air/fuel gauge. And I'm now watching both O2 sensors with it....I installed a two position switch so I can flip between either of the O2 sensors. Kinda neat. I mounted both this and the SAFC in the dash below my Alpine CVA-1005. Since there's all that extra space below there....it worked perfectly.

Yep, I ordered some more jet sizes for the Zex kit (not from them tho....from NitrousExpress...same jets). I'm using a 46 nitrous jet and a 28 fuel jet. That gives between 125 - 130hp. And the stock injectors, with just the help of the S-AFC and Supra TT fuel pump work fine.

I got a ProCharger 8psi supercharger. It uses internal lubrication, so I don't have to run oil lines or anything. I just have to change it's oil every 6000 miles. It will be a pretty simple install, right now I'm trying to find someone to make the 90deg mandrel bends in 3" pipe. I can't find anyone as of yet. I've already removed the clutch fan and shroud and gone with electric fans, so I've got plenty of room to put the thing in. I figure 8psi will be good for now. If I later want more power, I'll think about going with a turbo setup. What HP output you think 8psi is going to give me?


SR

 

280-300rwhp@6500rpm?
Just a guess.

Summit Racing may have 90 degree mandrel bends.

 

personally i wouldnt be tuning it w/o an EGT gauge... i have a S-AFC on my car, though i doubt my settings would apply to any of yalls. mine are about -15% all the way to -20%.

-brian
'92 turbo veilside rsp sc300

 

I have made a manual fuel mixture controller being a simple adjustable hose that allows an amount of air into the system AFTER the MAF. Simple and very crude, but effective and Cheap. This will only allow for a leaner mixture, not a richer one, though and is proportional, won't allow any fine tuning based on RPM, though.

Here's a question... If the MAF is just putting out a voltage based on airflow, why can't a resistor/potentiometer be used in line to adjust the amount of voltage the ECU sees, and therefore adjusts the mixture?