I have come across the overboost protection trap before, we have no overboost protection enabled, as far as plugs go they were new at the start of the day and got replaced at the end of the day with no or little improvement, I am suspecting the coils may be at fault, they are d585 coils but im pretty sure are knock offs and I think he may have wired the trigger ground to the same earth stud as the coil ground rather than back to the ecu, so that is a possible cause of the problem, I will go round shortly and take a log and see if we can identify any problems

 

Think I might have found a possible cause, I went and had a look over the coil wiring yesterday and found that the earth wires for the coils were wired into two banks leading and trailing with all 6 earth wires on each bank joined together and wired up though a single 5amp rated wire, They are all terminated at the same earth stud as the ecu, Im guessing that there is probably barely enough current for one coil on the 5amp wire and when the dwell time between coils start to overlap it falls flat on its ***, so Im getting the owner to leave the trigger earth wires there and seperate out the coil earth wires on individual 10amp wires and terminate them on a different stud, fingers crossed this will fix it!

 

I'm running a coil on plug sequential injection using ls2 coils on a 13b if you want to take a look at my msq

 

Thanks for the offer but I think our problem is in the wiring rather than the tune setup, Think we got on top of it today, rewired the coil earths and then measured the voltage at the coils with the engine running and only had 10 volts, we discovered that the cable that the power for coils and injectors had been taken from was the old fuel pump supply and had a resistor in the circuit, bypassed the resistor and we now have 13v and appears to be reving past 4500rpm now but now the tune is out due to the extra volts now available at the injectors, hopefully that is it!

 

The guys just did a bit more trouble shooting, they put a spark gap tester on before and after taking out the resistor, before it would jump 20mm and after it was out to just over 30mm, they then swapped out the suspect knock off d585 ls2 truck coils for some second hand ls7 coils and they had a much more powerful spark and would jump to about 40mm so I would suggest to people who are looking at using ls coils to take care buying them and make sure you are buying genuine, the truck coils we bought as we believed them to be the most powerful of the ls coils clearly the knock offs are not. They fitted 3 of the used ls7 coils to the leading positions and took the car for a drive and the back end tried to overtake the front, so fingers crossed we are ready to back to the dyno

 

Good news car has been back on the dyno and was falling flat again at 5000rpm I checked the voltage at the coils as the feed wire looked a bit on the small side, and it voltage was 12v at idle falling to 10v at 3800rpm and I have no doubt is was probably 8 or 9v at 5k! So we rewired that and then got a stable 13.6v and we were away made just over 400hp at 12psi and over 500nm of torque but the single plate clutch was giving up at 5000rpm so the tuner retarded the ignition to get it to rev through without the clutch letting go, So a bit more to come out of it yet, would defiantly benefit from a bigger turbo. Ill keep this thread updated when the clutch is sorted.
https://www.youtube.com/watch?v=mqhkG16Qgxs

 

Sounds good!

 

Sorry for the slow updates just hasn't been a lot happening with it lately, got it road legal today and went for quick drive so thought I would post a quick vid, still running single plate clutch and retarded ignition to stop it slipping!