Hello there. My brother just made a D15B Turbo setup I tuned in Crome. Its Stock internals D15B Engine with D16Y8 head with Vtec. 320cc injectors from Prelude and T25 turbo from nissan Silvia. 3"intake 2.5" exhaust with bigger cat.
I used to tune Crome Pro, AEM wideband gauge with LSU 4.9 and Phormula KS3 knock sensor.
I would like to show you maps I ended with. We also have EGT gauge. We would like to stay under 900°C wich was hard to be with 12.6 AFR so we was forced to go 10.6 AFR to stay at low EGT.
What do you think about? At 6000rpm and 8Psi we are at 12°ignition and EGT is still pretty much high (930°C). Compression ratio could be around 10:1. (by ferrea valves)
Spart plugs are at stock distance 1.1mm (0,044inch) and everything more than 12° ignition make Knock sensor to jell like detonations. We are actualy at 174HP and 200Nm. Measured by G-Tech RR.
I think we should be able to make more from 8Psi. Should not?

 

Are you running out of fuel on this? Those injectors seem pretty small. What duty cycle are you hitting near read line to keep it at 10s afr

 

It is actualy pretty high over 100%.

 

I would start with larger injectors and get those back under the “safe” level of 85% max

 

And except the injector duty cycle. Could the wide gap of spark plug make misfire which would be detected by knock sensor like detonation?

 

It’s plausible. What octane fuel are you using?

 

Natural 95

 

Yes. Also, ignition timing being too retarded will cause excessive EGT values, so add some timing to see if your EGT's go down and the knock goes away. Gap the plugs down to .030" or .75mm.