Supra Forums banner

1 - 14 of 14 Posts

·
Registered
Joined
·
582 Posts
Discussion Starter #1
Here I made a quick guide to those who are running the MAFT with SAFC setup.

Keep in mind im using the 2nd Gen SAFC with an 87-88 7mgte harness. Those of you with 89+ please find the correct diagram for your year 7m.



Here is the 87-88 diagram for those in need of it for reference.



Now let me explain some of the wiring.

The maft sensor itself has 3 color coded wires. They are Black for ground, Pink for 12volts IGN, and Yellow for the Maf airflow frequency. Route these 3 back to the MAFT unit, the MAFT unit should already have these 3 exact wires there, solder them together or use a splice.

The MAFT unit itself contains 10 wires. The 3 you just connected and 7 others.
The other 7 are as follows:
Pink - Switched +12volt power source
Black - ground (E2).
Green - Airflow signal (KS).
Brown - Air temp signal (THA).
White - RPM signal, connect the line leading from the ECU to the igniter. It's called 'IGT'.
Gray - HAC simulator signal, Connect to HAC signal wire at glove box (optional)
Purple - this wire triggers the AUX dial when the unit is set to RPM mode. Switch 12 volts to this wire to enable the aux adjustment.

Now the SAFC contains several wires, you will only be using 7 wires. These are as follows:
Red-12volt IGN
Green-RPM
Brown-Ground closest to ECU
Black-Ground farthest from ECU
Pink-Karmann signal OUT
Orange-Karmann signal IN

Side NOTES: for the grounds on SAFC to be hooked up correctly make sure you connect BOTH Brown and Black Grounds to the same Ground (E2) wire. Just make sure that there is at least 1cm between them.

The tricky part of this installation would be wiring the Karmann signal. The KS signal comes from the MAF's Green Wire. This Green Wire should connect to the SAFC's Orange Input Wire. Then you take the Pink Wire on the SAFC and connect that to the ECU's KS wire. Locate this on the ECU pinout diagram provided above. Please make sure you cut this KS wire so the Pink Wire can connect to it sending the karmann signal to the ECU.

Hopefully this helps some of you out. If you have any questions please feel free to PM me. Have a nice day

Charlie
 

·
Registered
Joined
·
582 Posts
Discussion Starter #3
Thanks I'd figure id share to help others out. I had to figure this out by myself. :)

charlie
 

·
Registered
Joined
·
400 Posts
So am i correct that with the SAFC install on a 87-88 supra you do not use the BLUE, YELLOW or WHITE wires with the install?

I'm wiring mine up now on a fields harness that was already setup for a VPC and SAFC combo but there seems to be extra wires.
 

·
Boost Dealer
Joined
·
981 Posts
um, the MAFT can act like an SAFC, so why do this mod?

Jeff
 

·
Registered
Joined
·
400 Posts
I personally don't have a MAF and i'm just wiring in the SAFC for the time being and later on I'll go MAF-pro. but i think i found my answer.
 

·
Registered
Joined
·
1,154 Posts
because the original maft sucks for tuning.
 

·
Registered
Joined
·
179 Posts
I know this is gonna sound stupid, but I have been wondering about this for a while. What is SAFC? I was guessing something like self-adjusting fuel controller?
 

·
got boost???
Joined
·
1,362 Posts
anyone have the ECU pinouts for 89+?
 

·
Pronounced Tek-DAY-us
Joined
·
1,596 Posts
I'm assuming this is to install the basic MAFT, just to be remove the AFM? I'm considering doing this soon and I have a dyno-tuned SAFC2 running great right now but I was wondering if I could ditch the Lexus AFM and swap in the MAFT with a 3" GM AF sensor, without additional tuning?
 

·
Registered
Joined
·
4,823 Posts
ok so how much psi can you run before fuel cut on a maft? and how much do they cost, this is a much needed upgrade for me lol
 

·
Registered
Joined
·
582 Posts
Discussion Starter #14
theres lots of variables concerning fuel cut before maft is installed and after maft is installed.

In my 7mgte mk2 when i was still on the afm, i could boost to about 13-14lbs of boost on several nights and not hit fuel cut. Thats with FMIC, 3inch exhaust, no cat, 3inch downpipe and hard pipes.

When i had the maft, i set it to clamp the HZ signal lower to get rid of fuel cut and i could boost up to about 16lbs of boost on the stock turbo. I never tried anything higher, which would have been a waste.
 
1 - 14 of 14 Posts
Top