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Needs side skirts and front bar support yet

Had it on the dyno yesterday.. had some normal teething issues and some not so normal once.. had oil leaks and coolant leaks everywhere...including a leak from the radiator :/ anyway sorted that shit out and then started the run in process. the engine was run in for a bit with some hard core load by holding it at 4000 rpm and then increasing the load, did that for a bit and its sweet... engine runs and sounds great. however once we started getting into the tune we found it would just missfire like crazy at anything over 4000 rpm and 12 psi boost.

Decs tried pulling fuel and timing out, adding fuel and timing and a combination of both, nothing made a difference. we tried gapping the plugs down to 0.5mm then 0.8 and then 1.2mm. none made it better. Coil packs were brand new 34 GTR Splitfires. only thing we can put it down to was faulty coilpacks.. so that effectively ended it for me. On top of this drama i have a clutch that doesnt disengage properly.

as you have just rewired it your miss fire may be being caused by electrical interference into the CAS wiring. running the 2 white shielded wires near the coil packs or to close to the injectors or anything that may cause electrical "noise" can make the ecu miss read the signals. when i wire rotaries it is very important that the ignition wiring and crank signal wiring are separate as they are prone to misfire then killing engines.

i have also had CAS die randomly and they will cause an under load fault. checking on the ecu shows it should have X amount of timing but checking with a timing light shows actual ignition timing far less. will be fine untill load is applied.

im sure you have checked it but fuel pressure will also cause a miss under load. not sure if you have put a gauge in it yet but as your lift pump was faulty you may still have an issue. depending what brand E85 you are using it may be killing your pumps/injectors. i know of local racers that have had 2 or 3 pumps go in as many events due to the brand/quality of E85. this is because E85 is Hydroscopic and will take in water. E85 manufactures are allowed to add a small amount of H2O to the mix but this can and will cause seizures of pumps and injectors.

hope that gives you a few leads if you done have it sussed already.

new loom is a haltech loom, comes with shielded cables for the CAS and triggers. Cas wiring runs under the intake manifold where as the ignition wiring runs from behind the head straight to the valley cover. I doubt thats the issue. We initially thought a faulty CAS or wandering signal might have been the issue... i held a timing light on the timing marks while decs ran it up to the point where it would missfire and the timing did not move around at all.

fuel pressure is spot on.. 40psi at idle and rises to 60 psi by 4000 rpm + boost pressure. does not move at all also.

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