240sx missing out at high rpms

[rickboy240sx]

I just recently did a full tune-upwaterpumpcap n rotorplugs n wiresfuel filter1 fuel injectori'm running straight pipes right now.... i put one on and it till did the same thing. It's hard to explain but here i go.When i first start it up it runs fine. after it ges up to temp it misfires when i press the gas 1/2 to 3/4 of the way down. i thought it may be the timing so i got a timing gun and ajusted it. it still back-fires mis-fires and idles like shyt.

would it be an o2 sensor...i'm not throwing any codes

[-RJ-]

temp sensor