Jaycar Boost and Fuel Control

[benl1981]

Thanks for the advice. I was only hoping to go to 10psi. But really I just wanted to not have the solenoid earthed all the time and have some adjustability there. I'll let you know how I go with the $15 needle valve. Do you guys have pressure gauges with peak hold on them? I was just going to pick up a cheap pressure gauge to verify that I'm not running too much boost when I play with the boost levels.

[resonance]

Yeah, I been meaning to ask, all you guys playing with the IEBC, do you have boost gauges? Does one need one with the IEBC?

[Oosh]

Yeah, I been meaning to ask, all you guys playing with the IEBC, do you have boost gauges?  Does one need one with the IEBC?

Yes and Yes, they're invaluable, you don't need a peak-hold one but it'd sure make life easier. But then if you do it way too high showing a peak of 20psi might mean it's already too late.

You just need to use a straight stretch of clear road, put the foot down and keep an eye on the gauge while setting it up, back off if it's climbing too high. Obviously you need to pay attention to your driving too so it's far better to have an assistant watching the gauge if you can arrange it.

[xRHETTx]

Hi guys,

I've just ordered a IEBC, DFA and hand controller that im going to build over the easter break (hopefully). As i have a r32 gtst, i suppose i need a r33 boost solenoid? One question, someone is trying to sell me a PCM VALVE PCM84-03 14956 45L00 of a r33 gtr. will this be ok, or do i need the solenoid off a r33 gtst?

Thanks,

Rhett

[Sydneykid]

Hi guys,

I've just ordered a IEBC, DFA and hand controller that im going to build over the easter break (hopefully). As i have a r32 gtst, i suppose i need a r33 boost solenoid?  One question, someone is trying to sell me a PCM VALVE PCM84-03 14956 45L00 of a r33 gtr. will this be ok, or do i need the solenoid off a r33 gtst?

Thanks,

Rhett

Any 12 volt boost solenoid will do, I would go for a "normally closed" style.

[funkymonkey]

has anyone tried the Digital Pulse Adjuster on the HICAS signal? I've made up a small circuit that can reverse the HICAS signal, but I'm quite convinced that with the right setup the DPA can be used to cancel HICAS completely.

[Oosh]

has anyone tried the Digital Pulse Adjuster on the HICAS signal? I've made up a small circuit that can reverse the HICAS signal, but I'm quite convinced that with the right setup the DPA can be used to cancel HICAS completely.

If you want to completely cancel HICAS why wouldn't you use a lock bar? <- NOTE: genuine question not retorical.

[benl1981]

Would the fuel adjuster work ok with a bigger turbo and front mount on R33. I.e if you were wanting about 200rwkw?

[Sydneykid]

Would the fuel adjuster work ok with a bigger turbo and front mount on R33.  I.e if you were wanting about 200rwkw?

I am intending to use the DFA and IEBC for 200 4wkw via a GCG Ball Bearing Hi Flow and I see no reason why it won't work. Plus I have achieved this power figure on a number of cars using an SAFC and the DFA is arguably superior.

[JaFF]

better than a SAFCII? would i be better off selling my SAFCII and getting one of these?

only problem is i don't think my mechanic would know how to use one ... I'm fine installing it myself but i don't have access to a dyno and if i did wouldn't know what i was doing!

[resonance]

I am intending to use the DFA and IEBC for 200 4wkw via a GCG Ball Bearing Hi Flow and I see no reason why it won't work.   Plus I have achieved this power figure on a number of cars using an SAFC and the DFA is arguably superior.

Hey SK, I've read all about the DFA in the SC book, and know exactly how it works (systematically and electronically). But how does a SAFC work? Does it just morph the incoming AFM voltage for differing 'load' points (AFM voltages) as the DFA does, or does it have other inputs such as injector duty cycle?

Does it suffer the same drawback of causing an advancing of timing due to the ECU thinking the mixture is lean if the AFM voltage is reduced? (Which can be overcome with another DFA being used to morph the CAS (Crank Angle Sensor) 0-5v voltage, or just rotating the CAS retarded a little)

I'm just wondering how it is better than an SAFC

I should be receiving the kits soonish from funky's group buy so am eager to get into the tuning.

[benl1981]

Wow. Ok. Thanks. Is that an RB25 turbo highflowed? ABout how much did that cost if you dont mind me asking and is there any more lag than the stock unit?

So you dont get the timing to far advancesd when trying to lean it out?

[Sydneykid]

Hey SK, I've read all about the DFA in the SC book, and know exactly how it works (systematically and electronically). But how does a SAFC work? Does it just morph the incoming AFM voltage for differing 'load' points (AFM voltages)  as the DFA does, or does it have other inputs such as injector duty cycle?

Does it suffer the same drawback of causing an advancing of timing due to the ECU thinking the mixture is lean if the AFM voltage is reduced?  (Which can be overcome with another DFA being used to morph the CAS (Crank Angle Sensor) 0-5v voltage, or just rotating the CAS retarded a little)

I'm just wondering how it is better than an SAFC

I should be receiving the kits soonish from funky's group buy so am eager to get into the tuning.

You will note I did say "arguably superior". The DFA has 125 load points and each load point has 100 steps, plus you can have wide steps or narrow steps (by changing the jumper). The DFA can do a mass change, at all load points, good for upgrading injectors or an AFM, then you fine tune each load point. The accuracy and stability of the DFA looks to be 100%, which is no different to an SAFC.

As for tuning, I have used both SAFC (a number of times) and DFA (once) and the tuning process was exactly the same. Use the up and down buttons to change the A/F ratios and use the left and right buttons to move to the next load point. I can't see that the DFA would be any harder for a tuner to use. It just has more load points.

In execution an SAFC and a DFA are exactly the same, they change the AFM voltage to "trick" the standard ECU into going to a different point on its A/F and ignition maps. The AFM voltage is the reference point for both maps, so whether you use a DFA or an SAFC you are going to get both fuel and ignition moving load points simultaneously. It could be argued that because of its superior number of load points and very fine tuning, the DFA is able to get the best compromise load point for both fuel and igntion. But it's still a compromise.

Sure you can retard the CAS to avoid pre-ignition under load and high boost, but that retards the ignition EVERYWHERE. This means you are compromising the speed of the boost buiild and response at times of low load and low or zero boost. In the end it is simply a matter of choosing which compromise you are happiest with. But it's still a compromise.

Hope that answered your questions:cheers:

What's next for my Stagea..............

This weekend I will be swapping the 3.25" exhaust off the R32 GTST (it's getting a 3.75" titanium one) onto the Stagea. Sometime next week I will slot the Stagea onto the 4wd dyno and see what effect the exhaust upgrade had. Maybe a little more tuning of the DFA and bit of boost tuning with the IEBC will be necessary. I am also doing the cambelt service and at the same time I will slot an Apexi adj exhaust camshaft pulley on. If it arrives from Nengun before I get it on the dyno, I will do a run at zero and then tune the exhaust cam timing for the best average power I can get. It's at 133 4wkw now, I'd like to see ~160 4wkw before I do the FMIC, turbo, split dump, hi flow cat upgrade.

[Angry]

being a complete novice to this....

i'm unsure of what i am to do ... i have a soleniod from a Greedy Profec E01 boost controller..and pressure sensor .. would i need to use this pressure sensor at all?

with the soleniod.. one wire is black one is red....i havent bought the SC book just yet,, but will .. but i think it would probably answer my questions .... anyways

has anyone used something similar with their IEBC install? is it better option than trying to source a rb25 one?

with the DFA ....adjusting the fuel mixtures at each loading points .is it from scratch or does it pick up on the standard points .. and u adjust that? again i should probably just buy that SC book and read it.

Matt

[benl1981]

So do you think for around 180-190kw on standard turbo that you need to adjust ignition. If you lean it out a little that is using the jaycar or similar.

[resonance]

being a complete novice to this....

i'm unsure of what i am to do ... i have a soleniod from a Greedy Profec E01 boost controller..and pressure sensor .. would i need to use this pressure sensor at all?

with the soleniod.. one wire is black one is red....i havent bought the SC book just yet,, but will .. but i think it would probably answer my questions .... anyways

has anyone used something similar with their IEBC install? is it better option than trying to source a rb25 one?

with the DFA ....adjusting the fuel mixtures at each loading points .is it from scratch or does it pick up on the standard points .. and u adjust that? again i should probably just buy that SC book and read it.

Matt

Angry, check up on the way the solenoid works because basically the only requirement of it is that it is driven by a 'PWM' (Pulse Width Modulation) signal, which just basically means a voltage that switches on/off (or high/low), and the amount of time it spends in the 'on' state versus the time it spends in the 'off' state is called the Duty Cycle. See http://en.wikipedia.org/wiki/Pulse-width_modulation

If it is, then you can use it. You won't need the pressure sensor, unless you were to hook it up to a gauge or something. The Jaycar IEBC only uses injector signal as an input, and the only output it has goes out to the solenoid. So it doesn't measure boost or know anything about it, but YOU have to, with a boost gauge. All it does is just open or close the solenoid a certain amount (which you set) for each 'load point' (which is determined from the injector signal duty cycle).

I recommend that if you want to learn more about ECU's, AWD systems, boost control or basic DIY/electronics, then buy the book, I have found that just the articles about engine management are worth the 20 bucks it is.

The DFA only adjusts the voltage signal, and by default doesnt adjust it at all, so it's very safe. It has a warning saying if you be silly and change points to be extreme values then you can cause damage, but otherwise you should be okay.

Also, anyone needing a solenoid, I believe my mate, 'halz' on here has a RB25DET solenoid which he doesn't need any more (has a PowerFC boost control unit instead), so PM him.

[Sydneykid]

So do you think for around 180-190kw on standard turbo that you need to adjust ignition.  If you lean it out a little that is using the jaycar or similar.

Every engine is different, but I wouldn't foresee any problem, there are plenty of RB25DET's around with ~200rwk using an SAFC.

[benl1981]

How much better is a power fc if your only going for 200Rwkw or running standard turbo?

Does it cost more to tune a power fc properly?

[Sydneykid]

How much better is a power fc if your only going for 200Rwkw or running standard turbo?

Does it cost more to tune a power fc properly?

I am only using the DFA because the Stagea is an auto, if it was a manual it would already have a Power FC in it. There is NO comparison, the Power FC enables me to tune everything, there are NO compromises, like the A/F ratio versus ignition timing that I have to make with an SAFC/DFA.

Yep, it will cost more to tune a Power FC. The DFA took me 20-30 minutes to actually tune, plus loading and unloading time, say $100 in dyno time. The Power FC would take me 2-3 hours (I am not a good tuner), so that would be $300-$400 in dyno time. But worth every cent.

[Niroth]

Sure you can retard the CAS to avoid pre-ignition under load and high boost' date=' but that retards the ignition EVERYWHERE. This means you are compromising the speed of the boost buiild and response at times of low load and low or zero boost. In the end it is simply a matter of choosing which compromise you are happiest with. But it's still a compromise.

What about those of us without boost??

Does retarding the CAS compromise anything in the NA cars. I've got a CA18DE in my little Nissan Exa, and I'd love to see if anyone has some mapping exmaples for the DE. Other than using a wide band O2 sensor, how do you tell if you're mapping is too rich or too lean. I know it adjusts it over 128 points, but is the adjustment relative to load for example 5% at any load point anywhere across the rev range, or is it a + x.xx voltage at any loading in the rev range. If its absolute and not relative, how would you ensure you are mapping correctly for light load and not too lean or rich for heavy load?

I've read the stuff on the jaycar website. Perhaps you should put me down for the book as well, I'm told its a good read. Can anyone help clear this up for me? Also, can anyone (who knows what they are doing) put up a map for a CA18DE (I know that different cars will need different maps, ie FWD vs RWD, but it'll give me a starting point)

Jase....