ca18DET fullybuild backfire problems 5Krpm i need opinions

[PeruchoS13]

To all CA18DET people that really know about the engine:

Setup:
Forged internals, FMIC, GT2860RS, Tomei procams 260 and tomei camgears, Tomei single valve springs, Haltech 1000, FPR aeromotive, 810cc injectors, Yellow jacket coils, new aftermarket lifters, new oem crank angle sensor (CAS), Turboxs high performance boost controller, walbro 255lph, Turbo back 3inch,

Fuel pressure set @ 50psi
Boost 15psi
Vacc reads 17 18


Here is the situation:

Before i changed the cranck angle sensor CAS, the car was getting stuck a 5k rpms and backfiring alot, also my mechanic could not set the timing with the timing gun, we decided to get a new CAS crank angle sensor and replace it.

After we changed it he could set the timing right and we went for a test. The car was getting stuck at 4k rpms but after that i could keep running up to 7500K , it solved the first problem.

WE did everything so we can take it to the dyno for a haltech tune session, as we thought the problem at 4k rpms was just ecu tuning.

At the dyno, with plugs ngk BPR6E gapped 28. the tuner solved the problem at 4k rpms but at 5k rpms the car was getting stuck and backfiring not letting go over that RPM, we tried many times until we decide to change plugs to a bkr7e v-power 25gap, and they lower the boost with the manual regulator, the car went over 5k rpms but got stuck at 6Krpm with less backfiring and the rpms needle went crazy.
Eventhough we lower the boost presure, it was still making 15psi, it looks like the wastegate of the turbo is too tied or something..

Tuner mention the ingnition was failing at higher rpms and he mentioned it might be the crank angle sensor or maybe ignition coils.... My CAS is BRAND NEW oem NISSAN so i dont think is that, I have this brand yellowjacket ingnition coils but i dont know how good they are ive been using them for 2 years are they chinese? I just purchased splitfire to see if i can solve the problem.

What i dont undertand is that when i tested the car in the street before taking it to the dyno, it was reving upt tp 7500rpm and just getting stuck for a little at 4k rpm, but at the dyno it was getting stuck at 5k 6k and not moving up from there...

Any opinions? any suggestions ?

Check this video
https://www.dropbox.com/s/tnv373rkwqyir ... 164528.mp4

[Sideways s12]

What do you mean by getting stuck? what size injectors are you using?

[PeruchoS13]

810cc Deatchwerks, when i say getting stuck i mean its no going over 5Krpm like iif it has a REVLIMIT got me? Im getting a new set of splitfire coils to see if its that.

[float_6969]

It sounds like an ignition problem. Did those coils come with any documentation telling you what the dwell should be? Unless they're not really uprated coils, the dwell should be different than stock, and so require a change in the setting.... Although now that I say that, if you're using a haltech, what ignition module are you using?

[boost_boy]

Sounds like too much pressure on those injectors. Why are you running so much fuel pressure? 50PSI of pressure at idle means a lot more fuel pressure under boost which is probably locking those injectors up intermittently causing your back fire. Adjust your fuel pressure to at least 40 psi and see how she goes.

[float_6969]

He's not actually running that much fuel pressure. The Detchwerks injectors are rated at 45psi IIRC. Before I had to pull the motor back out again, I was running 50 psi on 1200cc Detchwerks injectors with a Walbro 255 on E85 and I wasn't having any issues.

[PeruchoS13]

I agree qith float, shoudl be more coil problems, they didnt come with any manual or instructions... I purchased already splitfires to see whats the problems...