transmission went out again for the 2nd time in as many years. i run a powerglide behind a turbo 408 ford windsor. i got the transmission out last night and getting ready to rebuild it again but my thing is this... it runs out of gear right at the finish line, its turning 7200rpm to be exact at the line at 120/125 mph 0r so.(1/8 mile track)
the rearend is 4.10s and in on 28/10.5 tires.
should i change the gearing in the transmission to a little taller or should i change ring and pinion to a little taller?? im considering going to a manual g force or jericothen sitting the glide aside but im not sure if it will hurt or help me at the time slip puckup booth. input please from anyone with trail and error on this

 

not the transmission the torque converter went out. never seen this before. there telling me i need a 9 inch converter because the one i have is too small ( its an 8 inch ) and its early 90s so its outdated, does any of this sound strange to you? i thought the smaller the better when it come to race converters