My car is nearly leaning out. If I want more boost I need to...

[someonestolecc]

Hello,

My car was on a dyno yesterday and apperantly it started to ping. After a clean of the injectors it luckily pinged no longer (I wonder for how long).

The problem I do have is that it was (apperantly) close to leaning out. If I want to up the boost I run the danger of killing the engine/turbo.

My question is what sort of things will I need to check (incase they need fixing or upgrading) so I can safely run that sort of power level?

I realise a few things such as checking the fuel pump pressure and maybe upgrading the injectors are two things that need to be checked/upgraded.

Before I go to the shop and start getting bent over I'd like to know what I should get checked/think about to get more fuel into the engine?

If anyone's interested dyno sheets attached.

Thanks guys.

[Cubes]

So your making that sort of power and haven't upgraded your fuel pump yet?

Your living dangerously if thats the case.. All it takes is for the pump to start slowing down just a little and you will find your self replacing the motor

[someonestolecc]

I thought the fuel pump was upgraded to something beefier (GTR item perhaps). I'll have to ask the previous owner again.

I was 99% it was cos you can hear it at the back of the car whirring away when the car is on.

So.. I'll add that item number 1 - Check fuel pump pressure. Thanks Joel

[Cubes]

Get your self an adjustable fuel reg.. Possibly one of Unique's nice Nismo items.

[someonestolecc]

Adjustable fuel reg sits between the engine and fuel pump right? So you have a fuel pump that pumps a bit harder than usual then the fuel reg "holds" it back a little so you've always got the same fuel rate?

Zat right?

[Cubes]

Adjustable fuel reg sits between the engine and fuel pump right? So you have a fuel pump that pumps a bit harder than usual then the fuel reg "holds" it back a little so you've always got the same fuel rate?

Zat right?

A fuel reg limits the amount of fuel returning to the petrol tank.. In turn raising or lowering fuel pressure.

[someonestolecc]

Ahh. Thanks Joel.

Is there anything else I should check? Could it be the timing is too advanced? They said they can retard it a bit and that should be ok too.. less power but less danger of pinging.

So other than checking the fuel pressure, the timing, fitting a fuel reg, possibly bigger injectors what else should I do if I want to run more boost?

[Cubes]

It really depends what the tuner thinks..

If you are running out of fuel rail pressure then its the fuel pump.

If you have simply maxed out the duty cycle then you need more fuel pressure or larger injectors to use the potential of the turbo.

What turbo are you running?

That is the deciding factor for if you should jump in and go for larger injectors or to spend the $$ on a fuel pressure reg to squeeze a little bit more out of the current injectors.

[meggala]

tom the fuel pump is a walbro (255 litersd per hour I believe. was brand new whn the motor was fitted) the car is leaning out if under boost its is reading 12.5 or higher on the a/f ratios how much boost were you running or was it just as is.

the car doesnt seem to be running higher than 12 when under boost.

you will find the fuel map pretty linear even when the boost is up no need for bigger injectors as the car has 550 cc injectors. the injectors were cleaned and serviced when the motor was put in this car.

cheers

steve

call if you have any other questions

Ahh. Thanks Joel.

Is there anything else I should check? Could it be the timing is too advanced? They said they can retard it a bit and that should be ok too.. less power but less danger of pinging.

So other than checking the fuel pressure, the timing, fitting a fuel reg, possibly bigger injectors what else should I do if I want to run more boost?

[someonestolecc]

Fuel pump and injectors have been upgraded. I believe they are 550cc injectors and walbro fuel pump.

Turbo is Greddy t518z - rated for about 250kw i think?

I'm not sure anymore. Maybe I should have the timing retarded a tad?

[Sydneykid]

The dyno sheet says SR20DET is that correct?

[Cubes]

Say 550cc injectors will support 550hp on a 6cyl RB..

Thats roughly 91hp per injector.

If its an SR20 then 91hp per injector x 4cyls = 364hp.

200rwkw = 268rwhp which is approx 340-350hp at the flywheel.

I'd say 200rwkw is pretty close to the limit of the 550cc injectors.

[CEF11E]

if you have upgraded the injectors and fuel pump you have already had the stock computer remapped or you are running an aftermarket ecu. this being the case you should be able to correct the a/f ratios with a remap...

your power curve is nice.

need more details on the ecu dude...

[Dr_Drift]

The ceffy is running a remapped ecu, z32 afm, 550 cc injectors, and walbro 255 lt/hr pump.... It was tuned for mobil 8000 in Melbourne, maybe your running different fuel that could cause the light pinging?

As for running lean down low this is not a problem, as a matter of fact it's caused by running of the factory o2 sensor until it reaches a cerain afm voltage and then goes onto the correction maps.

We had this map running up to 1.4 bar reliably.

Feel free to pm me or call on 0425 818 755 if you ever have any questions about this car.

Doc.

[someonestolecc]

Thanks for the reply guys.

The topic is a bit mis-leading actually- the pinging stopped after an injector clean. They suggested maybe turning the base timing down a little too but I didn't wanna mess with anything just yet.

The dyno sheet says SR20DET is that correct?

Yes that is correct.

200rwkw = 268rwhp which is approx 340-350hp at the flywheel.

I'd say 200rwkw is pretty close to the limit of the 550cc injectors.

Interesting point you raise Joel. I always thought 550cc were more than I'd ever need. I will investigate this further - thanks for the heads up.

Dr what's your opinion on this? Should I be looking at bigger injectors?

need more details on the ecu dude...

The ECU is dr_drift's doing - so maybe you should ask him in this thread? (save the middle man ie. me).

The ceffy is running a remapped ecu, z32 afm, 550 cc injectors, and walbro 255 lt/hr pump.... It was tuned for mobil 8000 in Melbourne, maybe your running different fuel that could cause the light pinging?

Thanks for the info. I was using BP Ultimate, about 50/50 from different fills but both BP Ultimate - in theory should be 98RON and wasn't sitting in the petrol tank for too long (couple of days).

As for running lean down low this is not a problem, as a matter of fact it's caused by running of the factory o2 sensor until it reaches a cerain afm voltage and then goes onto the correction maps.

The standard o2 sensor plug is disconnected. Meggala said there was another one instead so I assume the old plug was just disconnected and doesn't attach to anything, leaving the other o2 sensor and wiring to do the work back to the computer. Does that sound about right?

If I wanted to up the boost dr_drift is it just a case of putting in an EBC and whacking it on a dyno and the computer should do the rest right? Because the guys at UAS seemed to think it was on the borderline of running lean and with any more boost on it wouldn't be good. On the other hand they didn't know the computer would adjust for that - so if it does well then thats fine.

Should I be looking at bigger injectors then to be on the safe side? What would I have to do to make the AFR say 11.5 just to be safe? Or am I just being paranoid?

Thanks again for your help guys.

[Dr_Drift]

Stopped pinging after clean - one of them must've had some crap in it then...

If the car does ping definately remove 1 or 2 degrees base timing for safety.

12.0 is on the rich side, i tuned it a little richer to Meggala's request. The 550's should be fine for 220-230 with comfort tuned as is. Wouldn't bother with the expense of a EBC, try using a GFB atomic, that worked quite well with no boost spike previously.

If your after more than that I'd suggest replacing the walbro pump with something a bit bigger like the Nippon Denso 280 lt/hr, and upping the injectors to 740cc

The O2 sensor should be plugged in? Are you sure their not cinfusing it with the cat temp sensor? the O2 is at the top of the dump pipe.

Doc.

[someonestolecc]

I'll get it dyno'ed again after changing oil filter, oil, fuel filter, sparkies. Hopefully the injectors stay clean and see how we go.

Yep the o2 sensor is plugged in on that side into the dump pipe. The plug they were referring to (which they thought was the o2 sensor) was on the top right hand side of the engine bay as you're lookin at it from the front of the car. Grey plug with a few pins in it - the plug is prolly about 1x1.5cm. I will take a pic when I get home I don't think it matters too much though since it is unplugged and when it was plugged in didn't make any difference on the dyno.

About when would I be maxing out the 550's and puel pump? Any point in getting a fuel reg to be safe?

[Beer Baron]

The Dr has given you good advice. 12:1 AFR is certainly nothing to worry about. I have 2 maps on my re-mapped ecu and the 'aggressive' map runs an AFR of 12.4:1 with NO detonation/pinging.

Richard

[someonestolecc]

Thanks for the reply mmm.

It was probably my injectors. I'm just scared of them getting blocked again. Hmm.

Cos my next upgrade was going to be EBC + cams and I didn't wanna add one thing to the mix and **** everything else up in the process.

[Sydneykid]

It was probably my injectors. I'm just scared of them getting blocked again. Hmm..

Use a good fuel filter and change it often and you won't have to wory about getting blocked injectors.