This is for you guys out there that really don't have a good understanding of how the SAFC works so I found what I think are very good links about the SAFC and other things applicable, but when you read all the facts involved in properly tuning it's really not that hard, but you need some knowledge about the following (open loop/closed loop, o2 sensor values, egt's, etc..) so you can understand how it is possible for the SAFC to work. Hope this helps so we can have more SR20DE(T)'s on the road tuned by someone other than JWT. I like the idea.

Here some info you might find interesting I have a SAFC installed in my 1991 SE-R I really didn't buy it for the SR20DE in my car right know because there just isn't a whole lot of power to be made in NA form with adding or subtrating fuel on a stock motor, sorry NA guys but rather I bought for my Avenir SR20DET but anyways here the info I was getting at on my SR20DE I had a place racing cold air intake. As per my SAFC readings I was able to flow a high of 62.4% air flow through my MAF. Without the cold air intake, my stock air intake system hooked up with a K&N cone filter could only flow 53.2% of the MAF capacity the filter is practically brand new to. See this is pretty good you will know when you MAF is being maxed out and when it is time for a upgarde then all you do is get you self another Nissan MAF that will work for you hook it up through your SAFC adjust your MAF sensor output number on the SAFC to the correct one if it changes for the MAF you just bought (it will tell you in the SAFC manual) and your ready to flow more readable air without having to send your shit to JWT, I never liked the idea of running a Ford part in my Nissan even though I like some Fords, just put a Z32 MAF and be done if you have a SAFC.

I will be running my Avenir SR20DET with a stock 1991 Sentra SE-R computer and SAFC of course. I can safely run the 370cc injectors because it is within the SAFC +/-50% range to be exact 388cc's would be 50% larger than 259cc injectors. So you want to make more power than that go get a Bluebird ecu for $200.00 witch is alot cheaper than JWT and is factory witch is allready programed for 370cc injector's and buy some 444cc or (555cc that will bolt right in) and tune it with your SAFC because it is within +/-50% range to be exact it can control 555cc injectors with a Bluebird computer. 50% larger 370cc = 555cc/50% larger 259cc = 388.5cc. Alot more cost effective if you ask me, only if you believe in the SAFC, alot of people with turbo's use it with good results for some reason in the Nissan crowd it hasn't cought on YET just search the Internet and you'll see.

http://www.alltrac.net/tuning/afgauge.html
http://www.roadraceengineering.com/newafc.htm
http://wac.addr.com/auto/obs/safc/safc.html
http://4g64.150m.com/turbo4.html
http://jdmfan.com/articles/a-f_meters/

NOTE THIS LINK IS A OLDER VERSION OF THE SAFC THE AFC BUT IS STILL INFORMATIVE
http://pages.sbcglobal.net/celica1/safc.htm

>Alot more cost effective if you ask me, only if you believe in the SAFC, alot of people with turbo's use it with good results for some reason in the Nissan crowd it hasn't cought on YET just search the Internet and you'll see.


Well.... the reason being, in short, the JWT option is easier/better and cheaper. Yeah, you can get the SAFC to work pretty well on a turbo car but you need to do some tuning. And for the tuning, you'll need dyno time with a wideband O2 sensor and probably an EGT would help too. Dyno time with the extra equipment for tuning will cost you probably $100 for 3 runs if you're lucky; it'll probably be more expensive. Since the SAFC costs $365 to start with, even with only runs you're already at $465.

I just read that the SAFC only has 8 data points which can be set at 500rpm increments. That's not exactly very good resolution. The motor would probably be smoother and run better with more data points, or like every 250 rpm.

Alright, so you got your SAFC wired in (which has got to be more complicated than just pluggin in an ECU) and the car is dyno tuned. So what's wrong now? The SAFC only modifies the air flow readings, but what about the ignition timing? You should probably get another black box to adjust the ignition timing with the new fuel maps to optimize the power. So probably another $300 or so. Then more dyno time, another $100 or so.

So... if you wanna use a SAFC, it'll get the car to run for a cheaper initial cost. It won't be optimized though and you'll probably have some compromises such as flat spots and such in the powerband since it has so few data points. As for wiring it in, it took me like 30 min. just to hook up my turbo timer and only 5 for the ecu. The time and "pain in the ass" savings right there is worth the cost difference between JWT and a SAFC. And then you gotta find time to dyno tune the SAFC; how much is your time worth? And even after paying for the dyno time and your time (and hoping it's done correctly so you don't blow your motor), it's really still not optimized because you haven't adjusted the ignition timing.

In short, I'm a lazy bastard, got the JWT ecu, plugged it in in 5 min. and been running perfectly since like it rolled out of the factory that way.

I think that the only way to do better than JWT would be to go with a stand alone system (AEM, Apexi Power FC, TEC III, Haltec, Motec, Electromotive) and then you better get ready for a lot of dyno time.

Khiem

Originally posted by charlie2020
I will be running my Avenir SR20DET with a stock 1991 Sentra SE-R computer and SAFC of course. I can safely run the 370cc injectors because it is within the SAFC +/-50% range to be exact 388cc's would be 50% larger than 259cc injectors. So you want to make more power than that go get a Bluebird ecu for $200.00 witch is alot cheaper than JWT and is factory witch is allready programed for 370cc injector's and buy some 444cc or (555cc that will bolt right in) and tune it with your SAFC because it is within +/-50% range to be exact it can control 555cc injectors with a Bluebird computer.

Right, but this is what causes the SAFC not to be worth it. SAFC + bluebird ecu and your in the same ballpark as JWT ecu, neverminding any dyno time and renting the wideband O2. As long as your not planning on having them burn you a new ecu every month, JWT is cost competitive ... just not time effective. :)