How to read boost on VAFC with no CEL. i got the solution
 

IAm a 3 year BBA student and all I do all day long at classes is thinking about my civic.
I ve came up with the idea of doing an Electrical Missing link ----. and put it between my VAFC pressure signal and the ECU signal.
As far I was using a Greddy missing link on the map sensor.
But on the VAFC i HAd no boost shown
Now i ve set my device to stop signal to 3V, because its a shitty cheap resistor, when i get 5V signal "in" there is 3.2V "out" but that hould be low enought as not to get a CEL.
I will be mounting this in an hour i'll tell you later if it worked or just screwed my ECU
Thats how the shema looks
http://www.funkyproductions.net/labs...t%20device.jpg

I hope it will work ;D

what u guys think anyway?

Re:How to read boost on VAFC with no CEL. i got the solution
 

I guess I don't understand the problem your solutions attempts to fix.

If you mean by "read", you mean display boost pressures on the LCD, then it already does that. It can do that because it intercepts the MAP input signal to the ECU and gets th true reading from it.

If, however, by "read", you mean correct for positive manifold pressure without the ECU seeing it, then it does that also. The fuel curving function of the V-AFC scales the MAP input signal, and outputs it to the ECU. Because of the scaling before the signal gets to the ECU, there i no CEL if a proper scale is done.

I personally run 10psi on this setup. When done correctly, it works.

Re:How to read boost on VAFC with no CEL. i got the solution
 

in his sig it says he's using stock injectors, so he's not scaling anything back and must be getting a cel from boost

Re:How to read boost on VAFC with no CEL. i got the solution
 

his sig used to say 4psi on stock injectors but now it has changed, ;D LOL!

Re:How to read boost on VAFC with no CEL. i got the solution
 

umm, no it didnt

Re:How to read boost on VAFC with no CEL. i got the solution
 

Rancid. The air flow increase vs stock injector output is horrible. Even NA, at the 1.3psi limit on a OBD0 setup, the 240cc injectors are at 85% duty cycle. The availability to pulse duration at increase at maximum boost is *very* minimal.

..scary setup, very scary..

Re:How to read boost on VAFC with no CEL. i got the solution
 

And he spelt zener wrong, you could just use two diodes in series, that would drop the voltage 1.6 volts.

Re:How to read boost on VAFC with no CEL. i got the solution
 

Normaly iam runing 17PSI
i just had one injector leaking and i have installed back the stock ones just for few days.
(before i get new ones )
Sorry you guys misunderstood me.

Maybe something wrong in my VAFC setup,
WHat do you guys mean by scaling?
Boost scale ca be either for NA cars or up to 1.5Bar or 2Bar
????
Anyway yesterday I didnt do it instead ive washed my car wish was more urgent, then that girl call me...
TOday i'll try to mount it and get ride of that missing link.
Thanx for the help
btw sorry for the diode spell but ive must have probably mistake it with the Ford Zhetec engine.

Re:How to read boost on VAFC with no CEL. i got the solution
 

You are attempting to tell us that you're running 17psi on stock 240cc injectors?

..interesting. Can you explain how to flow enough fuel to maintain ~12-13:1 air fuel ratio with the increased air density with 240cc injectors? ::)

..also, what MAP sensor are you using?

Re:How to read boost on VAFC with no CEL. i got the solution
 

You are mega gay.
he said he has 450cc injectors but temporary 4 psi on stock jets.
If you can not respond to the basic question please just say nothing

Re:How to read boost on VAFC with no CEL. i got the solution
 

I'm getting the same impression. I think what he is saying is that with the missing link being rigged between the Map sensor and the TB, the AFC digital pressure reading will cause inacurate output display. I dont think he is on the "hack". 17 psi is insane with stock injectors! I think that is impossible tho

Re:How to read boost on VAFC with no CEL. i got the solution
 

Iam running 17PSI on 450cc injectors !!!!
I ve got 2 fuel pump
lower compression ratio
Vafc hack
and many other ---- that gives me
low 14sec 1/4 mile on my 1.5L engine on stock tyres.
I have unplugged the missing link from the map sensor and now iam runing 10.5 PSI thats the max I can get without CEL
But i have discovered that the work of the engine is more fluent and more accurate.
THere is no chocking on dayly driving when Vtec engages.
When i Had the Missing link the max preessure on the VAFC ( display was about -60mhg when I have plugged in my electric device it was around -200mhg
Actualy i have to put a bigger Zener diod that would let more volt flow.

I have re-discovered my engine again.

And now i understand why you guys have your hack fuel setting straight all the way, because the o2 sensor is doing its job.

With the missing link ( i dunno how and why it is stopped)
and once iam boosting the fuel map where done by my own with up to O% at the end of the curve/
A bit rich sometime but that was the best Perform setting.
However what you guys do to run over 10PSI
hm..
How can you run 17PSI with your ECu and AFC reading 10PSI of BOost.
THanks for the help sorry if i didnt listed my setup :P

Re:How to read boost on VAFC with no CEL. i got the solution
 

the ecu doesnt see all the boost because the map voltage gets scaled back by running the 450s at negative percents

Re:How to read boost on VAFC with no CEL. i got the solution
 

Excuse me, but, if you actually read anything n this thread, he does not say 450cc injectors. But thanks, anyway, for your typical forum kiddie response. I'm sure we all appreicate your ability to eloquently maintain your subintelligence. :-\