Well I have the JDM P13 that is why I am asking.. I would love to go with hondata but the cost of having to buy a modded out p28 then get the system doesnt work for me. Using this method, even though its ghetto heehee, will allow me to use the bigger injectors and still be able to tune V-tech points. However I will still have the speed limiter issue.. Any good thoughts on the matter.

 

This is great. I think I will be able to save a little more money!!!! No FMU, just DSM injectors, resistor box. and an SAFC or VAFC. Either way this seems to be such a better way to go than the FMU. Does anyone have a wiring diagram on how todo this "hack" into the tb or wherever you do it. Im not too great with wiring, but Im sure if I had a diagram of some sort I could figure it out. BTW I have an OBD1 P72 if that matters......

 

hey with this setup could i get rid of my walbro intank fuel pump and just uses the stock one? or should i keep it for safty? thanks again

 

do you need to do the tps mod or not?also,what value resistors do you need to run the dsm injectors?how does it add fuel under boost?is that where the tps mod comes in?why hasen't anyone came up with a way to use a 2 or 3 bar map sensor?

 

your supposed to wire it just the way it supposed to i think. Correct me if im wrong. And as for the fuel pump, to be on the safe side, i would get a higher flow unit.

 

On stock fuel pump, FPR, 450cc injectors I was making like a 9:1 AF ratio at 7 psi... I figure you can get up to 8-9 psi with NO difficulties on stock pump with 450s. But if you put an FMU on the stock pump you're dead.

 

how about i use 370's , whats should the max boost be if i use my stock ls pump?

 

so this afc hack will work on any other turbo kit? Thanx for posting this up , its very indeed interestting i should tell my boost buddie about this. GOOD JOB MAN KEEP US UP TO DATE about anything new!!!

 

Now you had said hi an lo settings should be the same, but this can't be true. Maybe for a "rough tuning" but I always worried about this in the past. Example -

You use an aftermarket fuel pump, bigger injectors, 8:1 FMU and an AFC.

Say you set the AFC to do -8% from 3000 RPMS and up, and -30% from 1000-2999 RPMS. Now, you can be at 2500 RPMs, in 1st gear you will be under boost, but in 2nd or 3rd gear you are not, or depending on what % throttle you are giving it, etc etc etc etc.

There are a lot of variables. So wouldn't you need to get it on a dyno and have the hi and lo fuel "maps" setup appropriately (different) so the AFC will take load/throttle % into account as well as RPMs?

Hopefully I did not just make an *** of myself...

 

The AFC is not reading throttle input though, it is reading MAP sensor input on the throttle input wire ... So it /knows/ when you are in boost.

 

Over my head. I think I'm going back to the days of double pumpers and plate nitrous setups...

I think a 700 DP should do my 1.6 good...


[Modified by mplex2000, 5:54 AM 3/4/2002]

 

It's pretty simple... the afc "hack" is that you connect the MAP sensor to the TPS sensor input on the V-AFC. Thus it thinks the MAP signal is the TPS signal...

 

mplex, what about four barrel side drafts with the turbo... The best mass air flow sensor is a carburetor, hehehe... What is it called, draw through?

 

How do you hook it up to the tbs signal....could someone explain this....please

 

turner broadcasting system?

 

TPS sorry haha...as you can tell I am not too informed on this matter, but any help would be appreciated.


[Modified by SlowB16, 6:31 AM 3/4/2002]

 

Hehe, you just tap into the MAP signal wire at the sensor or ECU.. instead of the TPS wire the instructions AFC suggest.

 

Sounds simple enough. Some guy said he would do it for 50 bucks for me, so I will probably just do that. I dont want to mess anything up....thanks though Dustin

 

Why is Liam telling us to install it as normal then?

 

He's not. He is saying to not limit map input to the ECU. The AFC itself does the limiting.

You wire the TPS input on the AFC to the MAP sensor. Then say you are at 11psi of boost, map sensor returns 5V to the AFC throttle input, so it reads -40% off the correction factor, so it drops 40% off the current voltage output on the MAP sensor wire to the ECU. Thus it takes 5v, drops it to below 3v, and sends it to the ecu. ECU does not throw a check engine light because this is a valid MAP reading for full throttle, near 0 vacuum. Thus the ECU keeps the injectors at high pulsewidth, and with 450cc injectors you are injecting enough fuel to compensate for boost.

Dustin

 

so dustin with this set up..say if u had a non vtec sohc turbo..and maybe boostin lower psi..say around 5-7...if it was too rich u could run say -45 in the upper ranges right and this wouldnt **** up voltage drama with the map correct? everything would run smooth still u just leaning it out a bit?

"Could you remove a portion of the check valves so that the MAP reads "partial" boost. This could allow you to run lets say -20% on the AFC and still have some tunability for fuel vs RPM?
If you need -40% to get the MAP to work, you have no way to lean any part of your RPM band down if you were way too rich at any one point.

Curious."

this is a good question no one has answers..thats what i was wondering..with lower boost this might be too rich




[Modified by JaeOne3345, 8:45 AM 3/4/2002]

 

Not with the way i hooked it up. I have the AFC hooked up like its supposted to be hooked up. I use a STOCK honda map sensor without check valves or a missing link. The MAP goes into the AFC and then into the honda ecu just like if the car was N/A.

liam

 

no no no no no. I AM telling you to wire it up as normal. 100% normal AFC wiring. No MAP into the TPS on the afc computer. Thats just doesnt work right.

This is what im talking about.

AFC wired 100% stock outa the APEX manual
450cc DSM injectors (or something big like that)
AFC set at -40% in high and low settings
*NO* missing links or check valves on the stock honda map sensor

thats it. no other mods. You lower the map input so much with the afc you allow yourself room on the honda ECU for boosting around 10psi.

Ya follow?

liam

 

Oh, heh. I must have read it wrong then. Hmm, why would what I posted not work? (I don't own any sort of AFC anymore to verify).

Dustin

 

It should work how you said. But with this new setup you dont have to do anything like that. Just stock wiring. Using the afc to control boost with a map in the tps was just a huge hack..although it sorta worked.

Using the stock wiring and letting the honda ecu do the work is a much cleaner, simpler, and much less likely to break or for something to go wrong. Like my old built engine (R.I.P) which i blew because of a stupid vacuum line...this setup doesnt have any vacuum lines to break (yay).

liam