Give Enough Pressure To Bypass Ecu Protection

[Tangles]

Me? Im at 10psi at the moment....

Retuning the "project Stagea stealth wagon" (as my tuner calls it) on Tuesday at 10psi plus 1 power run at 12psi on my dual stage EBC.

Yes, I know 12 is bad, but Ive got a spare turbo sitting at home ready to be hiflowed! Plus I think it should be aok if I ever want a 10sec burst at 12, although I doubt that would ever happen.... maybe I might just do 11psi as the 2nd setting, not sure just yet.

[benl1981]

Yes you BK!!

Why are you retuning? Due to the front mount? Did you have an R34 cooler b4? I thought I remember reading that you did...

I'll be interested to see if there is much of a gain with the front mount at 10psi....i.e. in dyno reading.

I guess the main gain will be when you high flow and run a bit more boost.

[Tangles]

Oh, me!

Yup, just sold my R34 GTT Intercooler to a fellow stagea member.... found a Apexi front mount intercooler with end tanks that return to the original holes in the engine bay, and custom'd some aluminium pipes / silicone hose to suit (see Stagea intercooler thread).

So yes, retuning due to the fmic (plus all the parts Ive hoarded and have ready to install, as previosuly posted on pg1). Since putting it on the fmic has made the SAFC suck down 20% more fuel and car now has a 'wavy' power output..... so it needs a retune.

Wanted the sweet-arsed look of a fmic, but yet wanted to retain standard piping holes (ie didnt want to cut under the battery like a normal fmic kit). Got the Apexi 'Hybrid' (see internet for specs) unit from Japan 2ndhand off ebay - worth $1500 new!

Im hoping I'll jump from 141awkw to around 155awkw with the fuel mods, afm & ignition timing additions. Pretty much this year Im getting the fuel / air mods ready for next years hiflow job.

sorry to original poster for this nasty hijack!

Brendan

[Cubes]

Interestering.. its kind of related to the thread.

Ben, whats the lowest load point you are using?

4.91v I'm guestimating 14-15?

Give it a hard free rev.. Mine on the base map hits 100% injector duty over 4000rpm. lol

Edited November 17, 2005 by Cubes

[Tangles]

Cubes.... what if one injector 'fouls' suddenly? Boom? 100% cant be good on the injectors / engine. Maybe time for larger inj, or fuel pressure regulator?

rmahnovetsky - do a search in the Stagea section on Apexi Super Ignition Timing Computer, its SK's thread, very informative..... maybe you might want to think about grabbing one to work hand-in-hand with the SAFC?

Either way next friday I'll post up in the Stagea dyno section my dyno results using larger fuel pump, z32afm, nismo fuel adj. pressure regulator, high-pressure fuel lines, and the SITC / SAFC combo.

Brendan

[Cubes]

Hu? Thats the base map and I was saying to give it a free rev, It runs stupidly rich. Maybe the rb30 sucks so much air on a free rev; one reason I was aking to give it a free rev and see if injectors see 100% duty.

Obviously you don't want to be running injectors anywhere near 100% for any duration. Free rev is ok... they are hardly going to have issues hitting 100% for 2ms.

---------

Say the R&R does occur at around 4.5v..

Raise fuel pressure, adjust afr's to 12:1... Do this until the afm voltage going to the ecu is just under the 4.5v R&R.

Depending on power being made (airflow) you may not be able to adjust enough without causing idle issues.

Another better option would be to grab a 2/1 rising rate fuel reg.

Instead of raising fuel pressure 1 psi per 1 psi of boost it raises fuel pressure 2 psi per 1 psi of boost, this may help no doubt.

Try and see.

Those lesser load points now being used contain more ignition timing, pulling some out via the cas won't cause any big drama's.

Thinking about it now I would definitely use a 2/1 adj. fuel reg if I were to try this. Using the 2/1 reg leaves the light load and idle area's alone a little more. + an ITC work work very well.

I'm thinking not so much about the stock turbo, maybe a highflow thing. I think this could very well work using the bold to crack 240rwkw on a stock ecu.

Wouldn't want to run a walbro though.

Edited November 17, 2005 by Cubes

[Abo Bob]

If you pull base timing you will find the car sluggish off boost and lose responsivness.

If only dropping a couple of degrees then it shouldn't be too bad though.

To open the fuel tank you need a hammer and a stick of wood. Make sure you are turning it the right way and just bang on it. It can be pretty bloody tight. Put a little grease on the thread when you put it back on to make your life easier later on.

[benl1981]

Yeah I think it gets to load point 15. I have set rev limit to 5500rpm till I get a tune.

At times I can see Relatively high knock. .. Yesterday I saw 67 after giving it a hard time. I have never seen the engine light flash except once near when I hit the rev limit. I have the base timing at 15deg BTDC

Otherwise knock usually stays below 40. Is this scenario normal?

I'm only running 10psi so I doubt Id see 100% duty cycle - unless as you the PFC base map is very rich. Hoping a tune will help. You must be chewing a bit of petrol cubes if you are fanging it a bit?

What knock have others seen on the base map ??

Edited November 17, 2005 by benl1981

[Cubes]

The RB30 definitely uses more fuel when you are stuck up it all the time. General driving with a bit of a boot here and there fuel consumption is still 400-430km's per tank.

Worse I've seen is 350.

At the moment I see load point 16 from around 2400rpm and Z32 AFM voltage of 4.35v.

Its not tuned yet but soon. Knock is really good, I've been able to bump up the ignition map to 20-21degree's from 18 I think it was.

Knock 40 is o....k... I prefer a max of 30. With mine I've found over ~34, 1 degree more and it will occasionally jump to 50-60+.

From memory mine starts to show signs of detonation through unburnt fuel out the rear on the dyno yet not being able to hear it up around 70. I can start to hear ping at knock levels 90+.

Edited November 17, 2005 by Cubes

[benl1981]

Did the rb25 have more knock on the base map? Just wondeirng whether mine is normal or not. I guess maybe 1 or 2 deg retarded at certain load points should fix it.

I guess the base map is made for 100 octane fuel?

[Cubes]

I'm running the larger R34/VG30 turbine housing so this will allow more ignition timing due to less back pressure.

I have heard of others having slight knock with the RB25 base map.

Edited November 17, 2005 by Cubes

[rmahnovetsky]

man I have just got 50 email or so on replies to this thread.. Totally not related.

Thanks for the people who replied to my thread... Those of you talking about stuff that is way off topic please make another thread.. I would like to use this thread as a reference point for discussion and results

cheers

[Cubes]

No.

[benl1981]

It sort of relates.

Fact is running more fuel pressure for you is the wrong way to do it!!! It will make your condition worse. There's not much to reference.

[rmahnovetsky]

Is there a map or some sort for closed loop mode? Could you change the afm values to change the timming. Or is this just for open loop mode?

[Cubes]

Ben,

IF he hits R&R raising fuel pressure is the ONLY way to scrape in under neath R&R. Hopefully there's enough scope within the SAFC.

Or are we talking about 2 different things.

Edited November 17, 2005 by Cubes

[rmahnovetsky]

It sort of relates.

Fact is running more fuel pressure for you is the wrong way to do it!!! It will make your condition worse.   There's not much to reference.

<{POST_SNAPBACK}>

I have seen it done and have beaten buy a car that has used this technique.. It is something I will look into and investigate with trial and error. You dont get anywhere in life if you accept defeat.. As I said it has been done before with great results, so Im going to find the sweet spot and let other skyline owners know the trick. But if I never find it, it wont matter atleast I learn't something and others will benefit from it.

[rmahnovetsky]

is ther any links or picture of what the map looks like for the R33. Would give me a better idea on what is going on in there. I know the basics but the source is always better

[rob82]

You going to need a rising rate FPR say 2:1 to account for the decreasing airflow the computer will see but the increasing fuel that is required. Essentially all your doing is decreasing the resolution of the MAPs by not allowing it to see high amounts of airflow lucky the standard comp has good interpolation.

[rob82]

The standard R33 fuel map has really large numbers in the last two high load lines of the MAP the same for ignition but with less timing.