Power Fc Injectors At 100%

[a20089]

So I had an upgrade done with new turbo's etc by a Sydney builder/tuner.

I'm running into several problems running around Canberra.

1. The car runs rich, so much that it spits out carbon deposits and lots of them.

2. The power FC says it uses up to 100% injector, the sales rep at the tuning place recently told me not to worry about the figures they were not to be trusted (this from the same sales rep that told me that more PSI doesn't kill engines).

3. The car will occasionally and only under light throttle, give a kick like the fuel has been suddenly cut off then reapplied.

4. The fuel usage is very high, 300-330km per 50litres no matter what level of boost I have (11-18 PSI), before the upgrade I was getting 400+km on 15psi.

R33GTR 265kw at 18psi

2860-5 turbo's

Power FC

Boost controller

Cam Gears

Panel filter

Spitfire coils

Still running the same AFM, injectors, fuel pump

I realise that there are differences in climate from Canberra to Sydney, but the tuners claim to be world class. I feel I've been fobbed off by the sales rep many times and I'd like some ideas to ask the tuner etc when I next go down to Sydney. Why the hell should the computer running my car not know the correct injector utilisation. Opinions and ideas please.

[The Mafia]

wtf?

How about you just go and get it tuned by someone that knows what they are doing?

Its clearly over fueling..

[moonus]

thank god you have a hand controller. Do yourself and your car a favour. Go buy some bigger injectors and tell this sales rep that he is a tosser

[dmr]

it sounds like it's running too rich but the injectors can't handle it. i wouldn't advise going back there

[Trooper]

So I had an upgrade done with new turbo's etc by a Sydney builder/tuner.

I'm running into several problems running around Canberra.

1. The car runs rich, so much that it spits out carbon deposits and lots of them.

2. The power FC says it uses up to 100% injector, the sales rep at the tuning place recently told me not to worry about the figures they were not to be trusted (this from the same sales rep that told me that more PSI doesn't kill engines).

3. The car will occasionally and only under light throttle, give a kick like the fuel has been suddenly cut off then reapplied.

4. The fuel usage is very high, 300-330km per 50litres no matter what level of boost I have (11-18 PSI), before the upgrade I was getting 400+km on 15psi.

R33GTR 265kw at 18psi

2860-5 turbo's

Power FC

Boost controller

Cam Gears

Panel filter

Spitfire coils

Still running the same AFM, injectors, fuel pump

I realise that there are differences in climate from Canberra to Sydney, but the tuners claim to be world class. I feel I've been fobbed off by the sales rep many times and I'd like some ideas to ask the tuner etc when I next go down to Sydney. Why the hell should the computer running my car not know the correct injector utilisation. Opinions and ideas please.

I am having exactly the same problem, and getting the same advice from a very reputable workshop. I will be upgrading to bigger injectors in a few weeks, but still not convinced that will fix my fuel issue (20L/100kms, but I do not get to drive far at all with the car off cold start)

[a20089]

it sounds like it's running too rich but the injectors can't handle it. i wouldn't advise going back there

After paying $9K for the parts and tune, I'll be going back as many times as it takes them to fix it. I'm not impressed with their attitude and service at all.

[abu]

After paying $9K for the parts and tune, I'll be going back as many times as it takes them to fix it. I'm not impressed with their attitude and service at all.

Damn, you'd think you could get some service after spending that sort of money at a place.

There clearly not worth the trouble.

Edited September 9, 2007 by abu

[paulr33]

it depends when you are hitting %100 duty

if its at 7100rpm then its fine

if its at 5400rpm then its bad

do a test and see when its hits %100

also get another tuner to check over the tune and do a dyno plot with AFR to make sure its not leaning out (if its hitting 100% at 5400rpm for example then it wil be leaning out)

[The Mafia]

love the replies - The car is running rich so you all advise him to get bigger injectors?

GTR injectors can touch 300rwkw.

It needs a tuner that knows what he is doing.

[Trooper]

it depends when you are hitting %100 duty

if its at 7100rpm then its fine

if its at 5400rpm then its bad

do a test and see when its hits %100

also get another tuner to check over the tune and do a dyno plot with AFR to make sure its not leaning out (if its hitting 100% at 5400rpm for example then it wil be leaning out)

This is where things get interesting, a lot of people, who I would expect to know what they are talking about and a few that I actually trust as well say that 100% injector duty cycle while is not that nice will not do any damage if there are no knock issues. On the other hand there are many people that think it is the worst thing in the world to go above 85% duty cycle.

I have no knock issues (30 max on WOT), does not hit 100% unless I really push it. I am still upgrading injectors, FPR, coils as soon as I get the cash together.

21L/100kms is not nice on the pocket though, could this be JUST due to me driving mainly < 4km trips (i live very close to work/uni/shops) and the water temp is only just warm by the time I stop.

This driving style will change to min 20km trips on open roads next year, I am really hoping that things improve out of sight then.

[paulr33]

to go frther you need to find out when it hits %100

until then you cant do much

[Trooper]

to go frther you need to find out when it hits %100

until then you cant do much

Exact RPM I am not sure, but it is not until very high into the rev range, at a guess 6800+

I want to put in 555cc Nismos in, but do not want to make my short distance fuel economy even worse. Cruise seems to be fine, about 10L/100kms in more open driving.

[paulr33]

well the best way to progress is to dyno plot it with;

afr

fuel pressure

power

so you can see how the car performs and check afr's

you will then know if the %100 is causing an issue or not

youll also see power delivery. then once thats done, do a light load dyno plot so youll see what the light cruise / medium afr's are like

and lastly before you do anything else check 02 feedback is on and you have working 02 sensors. some tuners disabled them during dyno tuning and could possibly forget

[a20089]

Hitting 100% around 6500 at 18 PSI, but the engine revs to 8000. Hard to tell while driving.

Problem is driving to Sydney cleans up the shit coming out the back. Sales rep keeps coming up with the same line, "well GTR's are dirty motors, they have to run rich". Or "you will being getting worse fuel economy when you drive it harder". Doh..

How do I "check 02 feedback is on and you have working 02 sensors"?

it depends when you are hitting %100 duty

if its at 7100rpm then its fine

if its at 5400rpm then its bad

Edited September 9, 2007 by a20089

[rob82]

Take it to someone who knows what an engine is and knows how to tune.

[sl33py]

I saw this car the other night. One blip of the go pedal and the car literally shat a puddle of fuel out onto the tarmac lol. Ouch.

John, like I said the other day, I've had my car at like... 5 places (and multiple times each) to try and solve suspension woes. I know you paid a lot, but like others have said, when all's said and done, if they are too retarded to fix it, and spining you BS lines, I wouldnt be going back! I went back to Jax Quickfit like 6 times (because they had a satisfaction guarantee) before realising I was wasting my time because they are clueless. Cut your losses and try John @ Trojan He's had one of his personal cars in HPI, he's a heck of a lot closer than Sydney...

Hell, he might even look at it for free/cheap and give u his idea of what's wrong, if you're REALLY keen for the Sydney tuner to fix it. I've used this method when I deserve something to be fixed by the place I bought it, but they were simply too unskilled to see the problem.

[Nabil]

I wouldn't recommend running your injectors

at a 100% injector duty cycle as you risk detonation.

The reason being that as your engine consumes some cold (dense air)

it will require an equal amount of fuel for combustion, so if your

reach 100% duty at say 5000rpm you lean your AFR out and starve

the engine from fuel! As the injectors can no longer meet the fuel demand!

The std. injectors are approx 375cc so in general will

only support a maximum of 375hp at the engine.

To add to this, running a far too rich AFR will also increase

the level of knocking in the engine due to 'heat spots,'

caused by the build up of carbon deposits on the piston head

from over-fueling!

Good luck!

Go to a tuner

Not the local butcher! :laughing-smiley-014:

[Richieb]

Hmmm.

Which so called tuner was this?