Hi Team, I have a built S1 RB25DET that was installed in my HR31 in 2014. Engine has been running perfectly for 9 years mainly doing track work so lots of high boost and RPM. Runs 20 psi.
At a recent track day it started to miss once it got over 4500 and got worse as the revs increased. Could not get past 6000 in 2nd and 6500 in 3rd. Starts, idles and runs perfectly below 4500 under both light and heavy load.
So changed the plugs that had been in it since it was installed with a new set of BCPR7ES gapped to 0.75, fitted a new Du-Luck R33 coil loom (original had broken plugs etc) and purchased another set of Splifire Coils to try. Every time I changed something I took it for a test run and then moved on to the next thing.Thought all that would do the trick but no, this afternoon took it for a run after changing the last 3 coils and same thing. I can check fuel pressure (have to borrow gauge) and voltages of the MAF and TPS via my ECU Talk readout, but thought I would see what you guys had to say. Thanks.