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RB26/30 G4+ Extreme starting issues

iecku.tavea racing

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Hey there

My current project won´t start. The only thing it does is missfiring!!!

The setup is following in short:

RB26 head, +1mm oversize valves, 272° hks cams
RB30 block, 3.2ltr stroker
GTX4202 turbo, Hypertune inlet manifold
Okada Projects Coils, NGK Iridium plugs & HKS DLI
Fuel Injector Clinic 2150cc Injectors and 3x Walbro 450lph in the surge tank
Link G4+ Extreme

All In- and Outputs are working just fine so far. Checked everything more than twice. I also calibrated the trigger offset, all injectors and coils are firing while cranking. The ignition angle while cranking is the same like the real i see with the stroboscopic lamp.

So my current guess is that the crank rpm is to low (battery is fully charged), anything in the calibration is wrong (what i haven´t seen yet), the trigger reads wrong ( i know about the nissan trigger problems from other ecu´s) or anything else. I attached the last log and calibration.

I hope anyone could help me a bit. THere a hundreds of ours in that build and i really would like to fire it up! ;)

Your sincerely




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Hi there ,

  I have had a quick look at your PCL file, firstly under the CONFIGURATION setup you have the engine displacement at 65535 cc, it should be 3200 cc if you are running 3.2 litre setup.

You have fuel master set at 4 ms and you are running a trim of -25 %, very unusual especially considering you are only using 500 cc injectors, unless you are running 100 psi fuel pressure.

Did you actually activate the TEST ECCS SYNC or did you just leave it at default.

I always activate this and let the ECU count the widest slot itself.

Under Calibrate Triggers, I have never seen an RB engine set at a Trigger Offset of  280 deg.

Is your cam timing correct.

When testing the timing etc, DO NOT USE THE TIMING LOOP at the back of the head or the wiring going to coil 1, you will end up with inaccurate timing.

I always remove number 1 coil and fit a HT lead between the coil and the sparkplug.

Set cc's to 3200, put fuel master at 7 put the trim back to 0.

Carry out the Triggers setup correctly using the sparkplug lead method I mentioned.

Try to recalibrate and test from there.



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Hey guys,

thank you very much for your last replies! I have overseen the engine displacement setting. :) I´ll test and recalibrate ther trigger offset with your method, when i am back in the workshop. Cam timing should be correct, but i´ll check it once again! I also wondered that the trigger offset is that way off! Do you think the crank rpm is high enough. I just tested a original RB25 car yesterday and it seems to crank with twice the rpm!

Your sincerely


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Once again,

just have seen there is a new Pclink Version! :D That´s why i haven´t seen this setting! Does it mean, that the master/mastertrim doesn´t need to be touched, only for small "trims"?

Another question is, the widest slot. In the attachment you see my trigger wheel in the R34 GTR. The widest slot is more about +28° than the link measured 24°. Could i trust what the link measured?

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Hi , I just reread your initial post where you have posted that you have 2100 cc injectors.

My appolagies , I just looked at the PCL file and noted that you had 500 cc injectors selected under your configuration.

You need to also change the injector cc's accordingly.

Trust the LINK widest slot calculation, use only that value.

But this value will be obtained  when you enter the trigger set up and activate the Test ECCS SYNC.

Make sure you turn the fuel injectors OFF or disconnect them while doing this test.

You do not want the engine to fire or partially fire while in this test mode.

I would put the fuel master back at 6 and have o% trim for initial start.

You state you are using a Hypertune plenum, is it a plenum only or does it have a single throttle body on it also, or is it just the plenum and you are still using stock 6 x GTR throttle blades.

With 272 deg camshafts, either way it is probably advisable to use TPS as your Y AXIS on your MAIN FUEL TABLE, FUEL TABLE 1.



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 I´m back again. Thank you very much for your support so far. I recalibrated the trigger and made the changes to the calibration as you mentioned it. There were no sync or other errors. So i fired up the engine, but it was waaaayyyy to fat. I leaned out the master, its trim and made first adjustments to the fuel map.Not much to say, but at the end the engine runs unstable, little missfiring and it seems like one or two cylinders are missing. I once again checked camshaft timing, looked into the calibration, made injector and ignition tests. Everything is right for me. I attached the log and pcl. Perhaps you guys have an idea!

Yours sincerely


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for some reason my laptop has issues with LINK files at present..

I can not open the log file.

Anyway, I have created a new PCL file for you,

In the new PCL file I have also created a PC LOG SETUP for data logging for tuning purposes. .

Make sure you recalibrate the TPS and MAP sensors, make sure you press F4 and store to the ECU.

I asked some important questions previously, regarding the setup of your engine, but never really got the responses I required

For example a VERY IMPORTANT one was regarding the inlet plenum and throttle body setup.

 You state you are using a Hypertune manifold, does this use a single throttle body or does it still use the standard 6 throttle blades.

If you are using the standard throttle 6 x throttle blade setup with 272 deg camshafts you would have had close to 100 Kpa map which is equal to 0 IN/HG.

Your main fuel table was set up with MAP as the Y axis, so at idle with close to 100 Kpa you would have been running rich due to lack of vacuum.

I am only assuming this as I asked the questions previously and got no response.

So anyway taking a WILD guess I assume you still have the 6 x standard throttle blades and are just running the Hypertune plenum.

I have created a whole new PCL file for you to try.

This file is based on the engine still running on the stock 6 throttle blades.

If you don't have the 6 throttle blades and are running a big single throttle body don't even bother loading the file.

Kindly answer my previous questions so we know exactly what we are dealing with here, so we  can offer better help.

After allof this rich running etc, istrongly advise removing the sparkplugs and cleaning them or replacing them.

Turn the FUEL CONFIGURATION FROM SEQUENTIAL TO OFF or disconnect the injectors..

Crank the engine over with the sparkplugs out, disconnect the coils, crank the engine and expel the excess fuel from the cylinders.

Reconnect the injectors or turn the fuel back on from off to sequential.

Try to start the engine using small throttle openings like 5% or so, crank the engine and adjust the fuel master until it fires.

What fuel pressure are you running..

Anyway give it a go and let me know how you go.

When cranking and trying to get the engine running press F8 to manually start the PC LOGGER and press F8 when finished to save the PC LOG of trying to start the engine.



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Sry that i haven´t answered that question. Its the big single throttle version.

I found the problem why it runs unstable. Cylinder #5 & #6 are not firing. The plugs are clean and the exhaust pipe is cold. Picture below is left #6 to right #1!


For me it is a trigger problem or something similar. I run the nissan trigger calibration several times no change, as i already said that the widest slot is way bigger, than the "self diagnostic" 24° by the link!!! In ignition test mode all coils are firing!

Should i perhaps try a different nissan cas system from an r32 or r33???

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Hi iecku,

Ok so you have a big single throttle body, DO NOT USE MY PCL file then.

1. I PERSONALLY DO NOT LIKE TO USE IRRIDIUM or any TYPE of fine electrode PLATINUM TIPPED sparkplug to try and fire a new install.

They get wet with fuel and will very rarely fire correctly due to the minimal surface area of the tip of the centre electrode  to be able to allow a spark to jump to the ground strap.

Use standard style plugs for first start up, centre electrode has greater surface area for spark to generate from.

Plugs  4, 3, 2 and especially 1 are heavily carbon fouled.

These style plugs will typically always foul during a new PCL setup.

What generally happens is that the spark will fire  from the centre electrode and carbon track down the porcelain centre to the threaded end of the plug as it is an easier path to take to ground than to jump across a gap with a compressed mixture, especially when it is dense with excess fuel molecules.

If you have tested your injector and ignition outputs, did you remove the coils and sparkplugs, ground the sparkplug and fire the ignition output to prove that the cylinders, coil and sparkplugs definitely fire.

I notice you have SPLITFIRE COILS, excellent choice.

The HKS ignition amplifier you are using is also an excellent piece of gear.

I just want to know exactly what method you used to test the ignition outputs..


Sadly I have seen sparkplugs that look exactly like yours and the engine no matter what I did with the ECU presented the exact same symptoms.

If you look at you sparkplug photos ,number  6 and 5 porcelain , you can see that fuel is definitely being injected ass there is fuel residue on the porcelain, but you get no fire.


The GTR I tried to tune a few weeks ago, had his camshafts roll on him while doing the camshaft install.

I got him to do a compression test and he had 0 psi compression on 5 and 6.

While he was tensioning the camshaft bearing caps, he had the engine at TDC and no timing belt fitted.

As he tensioned the cam caps the camshafts rolled and the valves hit the pistons and bent.

The pure force of the valve spring acting on the cam causing roll back and hitting a piston is definitely enough to bend these valves.

Now I am not saying this is definitely your problem, however you have very similar symptoms, especially when reading the sparkplugs.




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Hi ,

 I forgot to add that the technician who done the job said, damn the camshafts did move when i tensioned them.

He had no idea that this type of damage could have happened so easily.

Sadly he also never realised that if he removed the cam caps from the front working towards the rear that the camshaft would also snap into two pieces at the last bearing journal due to valve spring pressure.

I commented to him that this is the importance of working from the centre outwards either side of the centre on assembally and disassembally.

He put new valves into 6 and 5 and this time I installed the camshafts ,timing  belt etc and showed him how to do it properly.

Put all 6 pistons at roughly half stroke so that no pistons are at TDC.

Bolt the head on and then install the camshafts.

With all 6 cylinders away from TDC it doesn't matter if a cam rolls  when tensioning the cam caps no valve will hit.

I also showed him that you can hold the camshafts on there ting marks with spanners and slowly bring Number 1 back up  to TDC and fit the timing belt.




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  • 2 weeks later...
  • 1 year later...



I just want to update you on this project. Hte R34 GTR RB32 GTX4202 is currently running very fine. The problem back in the days was a really bad done head job. If you have high lift ams you need to modify the heads to clear them. This job was done totally wrong. The valve lifters sometimes get stuck when the valve were closing, cause there had been some deburres and to less material to guide the lifters. We had ordered a total new head by a different engine builder and are now happy.

Now we already had some very funny tests on the track and found some other small problems on the setup. We had extremly fluctuating rpm signals around 6500+rpm so we limited the engine at 7k. We solved it with the ross performance trigger, which is really worth every penny. Also we have problems with the ET-S (AWD Pump) controlled via the link. We get pressure on the centerdiff to close, but it wouldn´t open if the valve for ET-S has a duty 0% after it. Perhaps the return bypass is stucked. So far car is fine, we are running 1,4bar peak and 1,2bar hold on spring pressure. +1bar boost is already at 3,5k!!!! I love good twinscroll setups! :-D


Just FIY!!!



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