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right well that would explain the sucky starting but how would that have affected the engine during normal operation? i would have expected the cycl #'s to fail or die given lazy injectors?

what do you mean by

Wolf3D has 16 tunning load points, Pfc only has 6.

6 load points? for what? where?

Lazy on idle as the pulse is soo short, especially with larger capacity injectors. The diagnoses found that if the injectors where given a tiny fraction more time impulse the problem cleared. That is why i had to send the injectors to a specialist, as these have to be tested at very low impulses and there are only a very few in VIC that could do such a test.

In our previous discussion you stated that the Pfc has only 6 load points and (i quote) "you can not see how a Wolf can have or use 16 load point". If you need an explanation of what a "load point" is please ask a tunner as i do not have the technical knowledge to explain it properly :P.

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Well keep me posted how you go Al. Sounds like your problem with idle might be simular to my own. I'm changing my fuel pressure reg this weekend to a 1.7:1 rate so I can run a low idle pressure to try and gain better injector control at low loads and idle.

I'll let you know how it goes if you want. Also, if your interested in swapping ecu maps let me know. I find it useful seeing how other tuners setup diferent sections of the wolfs tuning features.

Cheers,

Ian

I have a friend with a GT-t and PFC

compared to my car with the WOLF3D it does cold starts better

but not by much. As pointed out before, the cold start just takes a slightly longer key turn. A few more cranks of the engine before it fires up and idles. Not much to complain about really, and I dont have issues with idle on 450cc high flows guess it all depends on the tuner.

Well keep me posted how you go Al. Sounds like your problem with idle might be simular to my own. I'm changing my fuel pressure reg this weekend to a 1.7:1 rate so I can run a low idle pressure to try and gain better injector control at low loads and idle.

I'll let you know how it goes if you want. Also, if your interested in swapping ecu maps let me know. I find it useful seeing how other tuners setup diferent sections of the wolfs tuning features.

Cheers,

Ian

Would like that Ian.

My car should be ready in about two weeks, but i have been saying that for the last 2.5 weeks :P.

Send back that PM i just gave you, it is just to remind me, should i forget.

Well keep me posted how you go Al. Sounds like your problem with idle might be simular to my own. I'm changing my fuel pressure reg this weekend to a 1.7:1 rate so I can run a low idle pressure to try and gain better injector control at low loads and idle.

I'll let you know how it goes if you want. Also, if your interested in swapping ecu maps let me know. I find it useful seeing how other tuners setup diferent sections of the wolfs tuning features.

Cheers,

Ian

The whole idea of an aftermarket ECU is to control the injectors and timing among other things. So let me get this right your changing the mixtures with a rising rate reg to use a lower base pressure at low vacumm to control the injectors better???? Do you also realise that the silicone nomex diaphrams are alot more inconsistent and variant on to temp than a standard FPR that uses a steel diaphram. Your going backwards...... When are you going to put the carby back on???

Edited by rob82

With the fuel injectors you reach a point where the minimum time the injector is fired for is reached and the injector will begin to open eraticlly. This causes eratic fuel flow and it generally happens around the 1.1-1.3ms mark for most injectors. That amount of injection with the 440cc injectors makes for a 10:1 AFR at idle with my engine, which is just unacceptable. So I can put up with bad economy, or lower the fuel pressure which defeats the point of having the larger injectors in the first place.

A ratio FPR allows the fuel presures to be high at full boost to get the required flow thru the injector, but still low enough at idle and low load conditions that the car can have a pulse width that allows for stable injection flow.

These ratio regulators only become unstable when you push them above 80psi, which you don't do. A regulator will normally be setup at idle with the vacuum hose disconnected, and then the pressure adjusted to 35 or 43.5psi (depending on what you prefer/or injectors are rated at). That is not how you setup a 1.7:1 rate regulator.

In my case i'm aiming for 25psi max boost, and at that pressure I want 70psi max fuel pressure. So 25x1.7=42.5psi total gain from 0. So set my static pressure to 70-42=28psi, and then connect the vacuum hose which will pull the pressure down to about 10psi at idle. This means my idle pulse widths will be in the area of 2.6-2.8ms at idle.

Its not about changing the mixtures with the FPR, but obtaining a wider pressure range to gain better injection control.

Edited by GTST4Newbie

i always though rising rate fpr's made it easier to tune. oh well

go carby, pretty simple tuning. 1 screw for rich/lean one screw for idle..... then you just wind the dizzy out to advance the timing (joking)

load points aren't everyhing, as long as there are enough to tune the car then you should be alright.

I mean, motec have 40x21 maps, wolf have larger maps, doesn't mean it's a better ecu.... (well wolf have more rpm points, slightly less load points, but you get the idea)

16x16 minimum (as long as you can extend the maps, change rpm and load points etc.) is plenty of resolution to tune with. I mean nissan engineers obviously thought that it was enough....

I agree Merlin. The ONLY time i go into 250rpm resolution is to make idle stability better when switching the airconditioning on and off so that I can make the interpolation of the map points better during suttle load and RPM changes.

The rest of the time I tune in 500RPM resolution, and then I tune in 4th gear at 60, 80k's and 5th gear for 80 and 100k's to get that economical tune. When doing the on boost tune having a ton of load points makes little diference. In the end when your foots flat to the floor and your tuning that max load point your only changing values in 1 row... the 100% load point! Everything else in between just allows you to smooth the transition from 14.7:1 AFR at light cruise thru 13.8 under acceleration to 12:1 at full boost, which you can do with 3 load points.

With the fuel injectors you reach a point where the minimum time the injector is fired for is reached and the injector will begin to open eraticlly. This causes eratic fuel flow and it generally happens around the 1.1-1.3ms mark for most injectors. That amount of injection with the 440cc injectors makes for a 10:1 AFR at idle with my engine, which is just unacceptable. So I can put up with bad economy, or lower the fuel pressure which defeats the point of having the larger injectors in the first place.

A ratio FPR allows the fuel presures to be high at full boost to get the required flow thru the injector, but still low enough at idle and low load conditions that the car can have a pulse width that allows for stable injection flow.

These ratio regulators only become unstable when you push them above 80psi, which you don't do. A regulator will normally be setup at idle with the vacuum hose disconnected, and then the pressure adjusted to 35 or 43.5psi (depending on what you prefer/or injectors are rated at). That is not how you setup a 1.7:1 rate regulator.

In my case i'm aiming for 25psi max boost, and at that pressure I want 70psi max fuel pressure. So 25x1.7=42.5psi total gain from 0. So set my static pressure to 70-42=28psi, and then connect the vacuum hose which will pull the pressure down to about 10psi at idle. This means my idle pulse widths will be in the area of 2.6-2.8ms at idle.

Its not about changing the mixtures with the FPR, but obtaining a wider pressure range to gain better injection control.

The factory ECU has no trouble at all with a stable idle using 440cc injectors with standard fuel pressure in my GTR why does the WOLF struggle???? The PFC also has no problems. If there is any kind of mathematic calculation of cylinder fill behind the wolf then by using a ratio regulator you will definately put it off.

The factory ECU has no trouble at all with a stable idle using 440cc injectors with standard fuel pressure in my GTR why does the WOLF struggle???? The PFC also has no problems. If there is any kind of mathematic calculation of cylinder fill behind the wolf then by using a ratio regulator you will definately put it off.

Simplistically, the Wolf has slow injection triggers that can't open and close the injectors fast enough. This is not helped by the batch fire (2 X 3) which means half as much opening per revolution is required (compared to full sequentlial). Power FC's have the fastest injection triggers, they are at least as fast as the Motec M600. Plus they fire full sequential, same as the standard ECU. That's why you can run 1400 cc injectors with a Power FC, they are that fast.

:blink: cheers :)

Simplistically, the Wolf has slow injection triggers that can't open and close the injectors fast enough. This is not helped by the batch fire (2 X 3) which means half as much opening per revolution is required (compared to full sequentlial). Power FC's have the fastest injection triggers, they are at least as fast as the Motec M600. Plus they fire full sequential, same as the standard ECU. That's why you can run 1400 cc injectors with a Power FC, they are that fast.

:blink: cheers :)

Exactly!!! Plus the PFC and standard ECU take into consideration injector latency, try explaing that to the WOLF technicians. I have, there answer was thats what acceleration enrichment is for - completely missed the point.

There is no such thing as a fast injector trigger. If you want to get into specifics, the FC is designed to fire high impedance injectors or low impedance with a resistor pack attached.

The wolf does use a diferent kind of circuit design that allows it to directly fire both high or low impedance injectors. This is called a constant current source, and it also protects the ecus outputs from too much load being put on the injector outputs. It does not make the injector slow to open.

The 3 bank sequential double fire system does work. The only reason it has problems at idle with big injectors is the minimum on/off times for the injectors as I said above and on the previous page of this thread.

The rising rate reg is one way around it, and the other was would be adding a second injector bank weather that be a large 1500cc injector before the plenum or 6 additional injectors in each intake runner.

i'm having deja-vu...

There is no such thing as a fast injector trigger. If you want to get into specifics, the FC is designed to fire high impedance injectors or low impedance with a resistor pack attached.

The wolf does use a diferent kind of circuit design that allows it to directly fire both high or low impedance injectors. This is called a constant current source, and it also protects the ecus outputs from too much load being put on the injector outputs. It does not make the injector slow to open.

The 3 bank sequential double fire system does work. The only reason it has problems at idle with big injectors is the minimum on/off times for the injectors as I said above and on the previous page of this thread.

The rising rate reg is one way around it, and the other was would be adding a second injector bank weather that be a large 1500cc injector before the plenum or 6 additional injectors in each intake runner.

i'm having deja-vu...

Batch Fire is what Wolf uses, why because batch fire mode is Simple Like the Wolf.... FC Uses sequential, this is to help reduce emissions but is a much more complex setup. In saying this. Sequential will help with a smoother Idle and low rpm response. Power FC....

There is no such thing as a fast injector trigger. If you want to get into specifics, the FC is designed to fire high impedance injectors or low impedance with a resistor pack attached.

The wolf does use a diferent kind of circuit design that allows it to directly fire both high or low impedance injectors. This is called a constant current source, and it also protects the ecus outputs from too much load being put on the injector outputs. It does not make the injector slow to open.

The 3 bank sequential double fire system does work. The only reason it has problems at idle with big injectors is the minimum on/off times for the injectors as I said above and on the previous page of this thread.

The rising rate reg is one way around it, and the other was would be adding a second injector bank weather that be a large 1500cc injector before the plenum or 6 additional injectors in each intake runner.

i'm having deja-vu...

I did say SIMPLISTICALLY................

I can run batch fire on the Motec and it handles the 1100 cc injectors easily for a smooth closed loop idle. So it’s not simply a batch fire versus sequential question, the Motec injector control circuitry is obviously “faster” than the Wolf.

:P cheers :P

Paul; yes that is correct...

SK; it is full stand-alone unit but installed in a "piggy back" fashion... not sure how else I can explain this :P

it's not a stand-alone ecu. one simple test will confirm it. will the car run and drive correctly without the standard ecu in place? if the answer is no, then you have a piggy back. :P

Valid point Richard; but here's something from Tom @ BD4s:

"the V Pro is set up in a piggy back configuration for a reason. It retains a lot of the functions like ISCV and VCT, etc. also A/T. It also then can tap signals from a lot of the stock sensors and use them. But then it doesn't use the factory maps, it controls the engine "stand alone". So it is like getting the best of both worlds."

So maybe there's more to it than just a piggyback ECU.

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