95 camaro 4l60e will not shift at WOT

[95BlackZ28vert]

I have a 95 Camaro with a 4l60e and i am having a problem at the track at wide open throttle. It leaves great but does not want to shift unless i back off the throttle. Once I let out of the gas it will shift. I have a 383 lt1 putting down just under 400 to the wheels with a strange rear 4:11 gear 3600 stall trans specialties converter. Ive tried to shift manual and just leave it in drive no difference still no shift. The trans has just been rebuilt with a shift kit and new valve body. Im not a trans guy and this is driving me nuts! Any help would be appreciated. And by the way the trans feels ok just normal driving.

[NHRABill]

Please correct me if I am wrong here but the trans on these are electronically controlled and shift points are set by the PCM I was playing around with mine past week and tried performance tune which I am not happy with making it ottle I think the tables go throttle percentage and mph not RPM. I am just spit balling here hoping someone that knows what the heck they are talking about jumps in I am new to the software and ended up using a old school hypertech tuner to move program while I still learn the software.

[95BlackZ28vert]

I had the car tuned and this happened then i took it back and it happened again. So its been back to the trans guy twice and and the tuner twice and still screwed up.

[sweetbmxrider]

Mine was doing this my last track outing, I had some broken stuff in the trans along with metal.

[greenformula92]

Originally Posted by sweetbmxrider

Mine was doing this my last track outing, I had some broken stuff in the trans along with metal.

typical 4L60E. did you have the typical sunshell (I think thats what it's called) failure?

[sweetbmxrider]

Yup, though it was supposed to have been upgraded already

[3.4 grape of wrath]

Originally Posted by greenformula92

typical 4L60E. did you have the typical sunshell (I think thats what it's called) failure?

I had the same problem with mine at the track. I bought and installed a performabuilt level one 4l60E good for 500 RWHP and never looked back.