Since the SAFC II can control the A/F can it make my car increase fuel economy? The problem is that it won't be used for WOT, but partial throttle.

I also know that you can switch between 2 maps.

I was thinking I'd use the first map at 1000-2600rpm for fuel economy and 3000-6100rpm for power on the second map. Or it doesn't work like that?

I was thinking of tunning to 15-15.5 A/F for fuel economy. Too high perhaps?

The dyno place will tune the SAFC II.

The WOT will only be used for top end.

Also how does it affect warm up if I got it tuned for 1000-2600rpm??

And another question will the engine suffer if It's at 15-15.5 A/F, meaning damage it???

 

I would like to know this too...subscribing

also owners of the SAFCII...in case I need to remove the unit itself (to avoid theft at times), is there a plug I can just pull and take along with me? Just like how you remove a faceplate from the head unit to avoid theft...Also, if I drive the car without the AFC connected (if I forget to reconnect it after removing it) will the car just run on the stock program?

 

oh yeah another question...what gauge wire is recommended for SAFCII install?

 

I changed the questions a little to refine it.

 

If you bought it for fuel economy then sell it. It works on % throttle and will not work for anything less than 40% because the ECU will just reset it so forget it for economy.

There is a plug you can remove but its attached to the unit and is about 3 feet long but yes you can do it.

You cannot remove and drive the car because your MAF signal will be disconnected. You could possibly connect a jumper when you remove the plug.

The wires on the other side of the plug are made to connect directly to the ECU so you don't need any wire to install.

 

thanks for the prompt reply JIME! Can you elaborate more on this sentence though? I don't really understand it...

And as far as starting the car without the AFC connected...thats just the same thing as trying to start the car with the MAF disconnected right?

 

I haven't bought. Just seeking info first.

Then what can improve my fuel economy at those rpms????(besides removing weight)

 

I was reading up on a few things on the V-AFCII...there was something I came across but I freakin lost the page...something about Honda cars read the MAF differently....so when the VAFCII is hooked up to OUR cars...the reading will come out in a different measurement...or something along those lines? I'm sorry for being so vague, but can someone chime in on this?

 

the vafc 2 does not support hotwire (maf) so it displays pressure like map sensor.

 

The only wire that actually has to be cut is the wire from the MAF, all the others you simply connect a wire from the S-AFC to them.

The MAF wire is cut and one wire is fed into the S-AFC and the other end is connected to the MAF out on the S-AFC which feeds the modified signal to the ECU. So when you unplug the S-AFC the only wire that is interrupted is that one. A simple jumper will make the continuity from the MAF to ECU and everything should work as per normal.

If you look at the diagram you will see pin 54 on the ecu, that is the wire that is cut and the white and yellow wire from the S-AFC is connected to either end.

You could try hooking up a switch but I did that with disastrous results so I don't recommend it. I thought for a while I blew the darn thing up but after a few minutes the display came back.

So you would just have to put a wire jumper to connect the yellow and white wire. But I haven't tried this so don't hold me responsible.

 

I always thought I got great fuel economy as it is. Other than backing off the throttle a bit I haven't tried anything in that area.

 

For fuel economy: reduce weight, keep proper tire pressure, maintenance (clean filters, good plugs, etc), good gas but no higher than 91 octane on stock ecu

 

stock ecu w/o timing advanced at least on 00/01. 91 causes pinging and my base timing is 17btdc. i havent tried using 91 since bumping fp and backing out but i doubt i will try. 93 gives me the best mileage for my particular car. since it pings on 91, timing is pulled and power goes down.

 

come on...come on...That's like saying I'm okay with a slow car. And nobody will ever hear that for you.

I don't care about the freeway economy. I have corollas and civic sweating bricks. So far I can do 600+ miles on one tank if I were to go all freeway. I want mainly street fuel economy, that is why I asked for such low rpm. I'm only getting 22.5mpg on the streets.

 

Actually I drive pretty average on the street/highway, don't usually speed unless traffic is moving quickly then I just tag along. It amazes me that on the way to the track all the Honda's go like gangbusters but at the track they are somewhat subdued, maybe they use all their power up on the highway before they get there.

Its pretty hard to get good mileage at lower speeds, if it was constant its easier, but speeding up and slowing down are just plain gas eating tactics which are unavoidable on the streets. One thing I do with my auto is take the O/D off on the streets where I am doing 30-35 MPH, lugging the car at very low RPM is definately a fuel guzzler.

PS You are ok with a slow car.

 

If I only drive freeway I wouldn't be complaining. I always drive with the OD on, even on the street I can get into OD. People usually don't like driving behind me because at every stop light I accelarate slow but as soon as I hit the OD gear they are way behind me.

There is something that I can do, any ideas??? You always have answers

 

YEAH! thats what I remember reading....so what exactly does this mean to us Nissan owners? Does it pose any disadvantage?

 

Hey Jime, thanks again for the quick reply...I think Im just going to stay away from the wire jumper idea...I don't wanna get bad results like how you did with the switch....I'll just try to remember n hook up my AFC on before I go off and driving...

One more thing though....If I'm in a rush and I just TOTALLY forget to hook up my AFC...I won't do any harm to my maxima right? Like it would just be the same as trying to start a maxima with an unhooked MAF?

 

closed loop is based off the o2 sensors so to get better gas mileage you would have to modify those signals, not the maf signal.

 

i dont see it as a disadvantage. of course the pressure reading (psi) means very little if anything but having the 24 points instead of 12 is enough for me to buy over an safc2. the only thing that i dont like about my vafc2 is the wires are shorter the safc and it wont even come close to going in the sunglass holder. only a minor inconvienance before the wires get extended.

 

Correct exactly the same.

You realize of course that you have 2 maps to switch between and I really don't think the S-AFC is a high theft item. I had mine stuck to the dash with velcro so if you did that you could just stick it under the dash when youi got out of the car if you were worried about someone stealing it.

 

Ouch....may I ask what gauge wire you used to extend them? Sorry for all the questions...its cuz I just bought one

 

Sounds like a good plan...I'll take it into consideration....oh yeah, what would switching between two maps serve? I plan to take it to a dyno shop for tuning (WBo2)....Should I ask them to make

1. Super aggressive map strictly for drag racing
2. Semi aggressive map great for daily and also occassional street race

 

oh yeah...does anyone know if 1hr is good enough for a good dyno tune?

 

Everybody is fast while i'm the slow guy.

 

Should be ok ...

@ what speed?

 

65mph. And on cruise control. If I don't do the cruise control the fuel economy drops. My sweet spot is 55mph but I can't do that on the freeway. So I go 65.

 

600 is absolutely crazy. I've never seen over 450.

I like the idea with a different map after say, 3500 rpms. If it's possible.

 

600 miles!?! How big are those altima gas tanks?

Manny, when do u plan to hit the dyno? Also where did you mount your AFC? I need some ideas on to where to mount it...the sun glass holder can't be an option since people say the wire won't reach up there...

 

Is that 600 + miles on a VQ

 

You must have a VAFC...
I mounted mine under the A/C controls. ... Keep in mind mine is auto, and it only remotely gets in the way when I go into Park....

 

I need to get cruise control back...

 

Hmm...so its right in front of the coin holder/ashtray? I might be able to get away with it since I do have a short throw shifter...I'll give it a shot and see if it clears my shifting...

and yes it's a V-AFCII...people say the wires are much shorter...I'll check it out once I get it in the mail on Tuesday