DSM AFC - A New Way Of Thinking...

Can you make the 440s work with the DSM AFC?

I mean...I made it work with the MPI but they are a pain in the ass
 
MSP608 said:
it doesnt stall bc the car goes into vac. it stalls/dips bc the maf reads air thats actually not going into the engine so it dumps in fuel. i dont see you being able to modify it so it doesnt over rich itself between shifts but then not go too lean at idle.

Yeah, it stalls because its venting air already measured by the MAF, but with a MAP sensor setup, it wont read mass flow, it will only read absolute pressure, so it wont stall.

Also like the other guy said, probably the HKS EIDS may solve the stalling issue, it will stabilize the voltage when you release the throttle. I think I have a log recorded of the difference...it shows the voltage of that metered air being vented vs what it shoould read..ill try to find it.
 
Here it is, to place you in the scenario, this is just after the end of 3rd shift.

The red line is what the MAF is reading.

I let of the gas at the end of 3rd gear, the BOV is venting. The blue line is what the MAP reads (vacuum). As you can see, the MAF believes that air is being used when its not (its being vented)... So ideally, the blue line is what you want, what will make the ECU happy, what you see when recirculating bpv, thats around 2.3v...see how they merge at the end...thats when the bov stops venting. No engine stall.

But to make the car run good, what you want to do is mimic the MAF as close as possible thru all the ranges (**if using stock injectors), vacuum and boost with variable loads. So with percent values, adjust voltages accordingly and you are done!
 

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I don't think anyone's tried it yet. I know a couple of EVO guys have used it for sure. I like your thinking with the AFC though, very creative and pushing the limits of what it can do. Personally I just relocated because cutting and buying some silicone connectors was easier than pulling my hair out in front of a laptop!!!
 
Found one on NASIOC for $80 shipped. I'll buy it and try it out. Subie and EVO guys use them no problem.
 
Maxx Mazda said:
Basically, can the DSM AFC be used to control fuel trims while in vacuum? That way, I can do away with stalling without having to relocate my MAF. If I can tell the car how much fuel to get as soon as the car enters vacuum, it won't stall.

Well, the car is usually running in vac, but I assume what you're on about is that you'd like to go WOT until redline, let off the throttle, throw it in neutral, and not stall, correct? And I'm assuming you're running a BOV that's vented to atmosphere?

Well, assuming your car is functioning properly, you're not running ANY fuel at all as soon as you let off the throttle (assuming you're above idle speed). So basically, what you want to do won't work.

In a nutshell, if my assumptions about your car and what you want are correct, then the best way to fix the issue is to relocate the MAF.
 
kooldino in your sig pic are you running 2 maf's

and i hope you can figure this out maxx because i hate stalling with my bov
 
GhostMercury said:
kooldino in your sig pic are you running 2 maf's

and i hope you can figure this out maxx because i hate stalling with my bov


why dont u run the dual setup?
 
Well, my main reason for keeping my MAF where it's at is that I have some REALLY nice MAM intercooler pipes that I don't wanna hack into. Plus I mounted m BOV pretty close to the TB and I don't know ic I could even fir the MAF by the time I got al lthe couplers and s*** in there.

I'll try the HKS EIDS and be the guinea pig. If it works, then we all know. There is a ton of EVO / STi guys using it already.
 
Maxx Mazda said:
Well, my main reason for keeping my MAF where it's at is that I have some REALLY nice MAM intercooler pipes that I don't wanna hack into. Plus I mounted m BOV pretty close to the TB and I don't know ic I could even fir the MAF by the time I got al lthe couplers and s*** in there.

I'll try the HKS EIDS and be the guinea pig. If it works, then we all know. There is a ton of EVO / STi guys using it already.


all you do is weld a small nipple onto the hot pipe and hook teh bpv up to it. keep the bov right where it is. you dont have to hack up your pipes.
 
mspHtown said:
all you do is weld a small nipple onto the hot pipe and hook teh bpv up to it. keep the bov right where it is. you dont have to hack up your pipes.

I'm not running a BPV dude. BOV only.
 
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