having problems shifting 2,3 gear at 6300rpm redline @ 6700 and shifting 2,3 at 68mph and moved the rpm to 6000 and to shift at 65mph and it shift's good i have 07 chevy nbs with a 4l65e 3800 pi single disc stock oil pan fully built tranny i want to know what's the problem

 

yo forgot to add that it backfires. Did it do it on the last run also wey?

 

no it did not backfired shifted good @6000 rpm dut rpm were to low like
@ 4500

 

ran a 11.542@ 119.68

60ft 1.733
1/8 7.448 @95.56