are you using anything to retard your ignitino timing?

 

Liam... I just wanted you to know that you RULE!!! I just did the MAP mod tonight, removed the ML and changed my AFC settings to:

1k-4k = -40%
4.5k = -37%
5k = -33%
5.5k-7k =-30%

Transition is absolutley SEAMLESS!!!
Dude, I haven't been this happy with my car's drivability in ages! So far the highest i've taken it is about .57bar on the AFC. Tomorrow I'll cross my fingers and hope I can squeeze .7 bar (10psi) w/o a CEL. Thanks again dude!

Oh and thanks to dbman for starting this whole "AFC hack" train of thought

 

Well I guess I owe it to myself to try hooking it up this way although I still can't quite grasp how its working better... maybe my brain is just shot from a long week at work. I'll try it out this weekend.

Oh and I forgot to mention I was running a JRSC-style TPS relay so as soon as I crossed over into boost it delivered a WOT signal to the ECU to force open-loop operation; that made the whole thing a LOT smoother.

 

Weeeell, I guess it's time I gave this puppy a shot. I don't know that much about the AFC settings other than the fuel (wide throttle?) and of course VTEC settings. I think mine doesn't let me adjust the narrow throttle settings, do I need to change anything? Basically what I'm asking is this - what is EVERYTHING I have to do to make this thing work. Also, I only have RC 310 injectors, do I need the 400+ injectors for this to function correctly? I'm only running 6 lbs boost but I'm getting ready to move up to 8.

 

i bet those 310's would be just fine

 

Thats very cool you posted this --

I setup a customer's car like this a few months back -- first i did the two map sensor idea then i went right to the single map and TPS, like the AFC is supposed to run.

The car is a 00 Si and the obd2 kept bitchin at me and throwing codes, so this coming week im supposed to convert it to obd1 (im using a p28 chipped with a b16 program & a 9k rpm revlimit) and i actually plan on putting a greddy black box (voltage limiter) on the car. However, this will not go on the MAP sensor, rather between the AFC and the ECU. This will make it impossible for the afc to add more voltage than the ecu can handle. While this is a good idea in a way becuase it wont throw a code, it might prove to be an issue as the afc will suddenly stop adding fuel, especially when i want it to keep going. The customer is a kid who is very patient which allows me to play with his car, but he doesnt want to spend the money for a hondata. As a result he would rather use what he already has (including an MSD 6BTM) so i figure why not? I work on the car after hours for fun, and he brings the

 

awesome! Thats what i wanted to hear! I was really happy with it also. It drives just so awesome.

liam

 

The 310cc injectors should work..but you are not going to beable to boost as much as your cant give the afc as much of a negative value. I would give it a try and see how much you can boost before you hit a CEL. If you want to run more get some DSM 450cc injectors are they are only $50 used on thepartstrader.com / or dsmtrader.com..and you will need a resistor box if you dont already have one.

Other then that all you need to do with the afc is set both high and low throttle to your negative values (-40% in my case and whatever you need for your 310cc injectors). And thats it...you hookup the AFC just like you normally would.

liam

 

I hooked up my friends car, a 98 civic LX odbII with a y8 conversion. He is running the same setup as i, running 9-10psi of boost and not throwing any codes. Hes running DSM 450cc injectors also. The y8's have a knock sensor and all sorta of other sensors which seem to be happy as every (amazing amazing).

Good luck with your customers car i would like to hear how it goes.

liam

 

OK i need a little help here. So your saying hook up the afc as normal and set the valuves to what you say. Then remove old injectors and get 450s witht he resistor box. and then im good to go? DO i need to remove my boost dependant fuel pressure regulator? This sounds like an awsome mod. Is there anything else i need to do this? or am i missing anything? thanks again oh my car is a 2000si with drag3 kit. thanks again


[Modified by turboex, 3:58 PM 3/2/2002]

 

If you use the 450's I belive you need the resistor box (if they're peak/hold).

As for 310's, I dunno if you can cut it with 310's. It's really dependent on how much boost you want to run, but with the AFC set to trim like -30% on 310's, I don't think you're gonna deliver enough fuel for 9-10psi of boost without running very lean. Maybe if you added 6:1 FMU to the mix you could get away with it, but not just on injector alone.

 

This is the VAFC right, not the SAFC?? Or does it not matter?? Thanks for answering my stupid ??????'s

 

uhmm what does that mean in ENGLISH?

 

Are you talking to me? I am asking does it matter if you do this with either the Safc or the Vafc? Or does it work with both of them?

 

both work the same..you can use either. i have a safc and my friend uses an vafc.

liam

 

Thanks man. Which one would you say is better for a FI car. I was thinking the Vafc, but Im not really too informed....

 

Well unless you want to change the VTEC engagement then youshould probably go with the S-AFC. It's supposed to be more configurable. I don't know how, but it does cost more,LOL!

 

Would this work for someone with a non turbo application, but has DSM injectors waiting to be put it. My car already has a resistor box so that would be easy to do..

Also is there any way of getting around a speed limiter with the APEXI VAFC?? And why is the fields unit able to do it?? That would be a great help if you guys could figure out that one for me.

 

Yes, your application would work also. You'd need to adjust fuel delivery as usual with your SFC.

The FIELD unit removes the speed limiter present on Japanese, er, JDM ECUs. ECUs from US market cars have only the rev-limiter, no speed limiter.

 

Yeah that is what I thought. This whole idea seems much more sufficient tahn the FMU and chack valves!! Thanks though

 

Are you sure about that?? I always thought they were identical except the S-AFC didn't have the VTEC cross over feature (and corresponding dual fuel map's for Lo-cam and Hi-cam).

 

Nope, I'm not sure, hence the "supposed to be". The S-AFC does cost more though. Like 15-25 bucks depending on the retailer.

 

I am pretty sure that the Safc is strictly fuel, obviously, and it has alot more settings and features for tuning of the fuel curve.

 

i like the safc better personally...because i can do the "blue wire mod" (so i can read the o2 voltage with the afc)

liam

 

The VAFC just adds fuel in and outa vtec and vtec switch point of course. Just honda vtec stuff.

liam