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R34 skyline dwell timing issue


Chrismac

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Hello. Hoping someone can shine alittle light on my issue. The car is a 99r34 skyline gtt with the Rb25det neo. I’m running the link g4+ ecu. The car last year was running 18psi boost and ran great And now this year I uped the boost to 25 psi and it started have bad misfire above 5500 rpm.

Fuel pressure is at base 50 psi on a 650cc injector at around the 90% duty cycle so I’ll be upgrading those but as for the issue I’m having ,something doesn’t look right with the dwell timing. The coil packs are new oem from Nissan last year and I don’t see any issues on the coil boots but the dwell timing setting seem to be really low. The setting are untouched from the base map. If I’m understanding how the dwell works, shouldn’t it go up in higher rpm? 
Any help on this issue will be greatly appreciated 

the is making about 480rwhp.

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You can try more and see if it helps, whether you get any increase in ignition energy or not will depend on whether the current dwell is fully saturating the coil or not.  No it is not normal to increase dwell with RPM, the main factor to compensate for is battery voltage.  The reason for the second axis is many coils overheat if you run them near full saturation for long - so the RPM axis (or MAP in some cases) can be used to allow you to give the coil less dwell when cruising etc to allow the coils to cool, then only give them the most around peak torque where the most ignition energy is required. 

No personal experience with those coils, but 25psi is about the limit of stock RB neo coils from hearsay.

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7 hours ago, rrob said:

Grab a set of r35 coils and bolt them in with a spacer and a longer bolt. Wiring is the same connector and pinout.

Thanks for the info. I though the r35 coils were different wiring than the neo coil packs

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