I got a weird thing going on with a freshly rebuild 727 and a new 9.5" converter behinda 500CID with a roller camshaft making some nice horsepower! Street car, no race car.
First converter flashed at around 4000RPM although we expected it to be around 3000RPM. Otherwise the 727 shifted nice. (TF2 Kit, red racing clutches etc.)
The converter maker made a new converter and said it should get 800RPM lower flash stall.
The 727 was inspected after a few 1000miles and it looked brand new! All perfect!
Test drive a while ago with new converter showed 200RPM lower flash stall than before, although 800RPM were expected!
Converter builder really can't explain it and he said it's almost the tightest converter he can build in 9.5".

Now my question: anyone of you ever experienced somethign like that? Could it be a to low converter oil pressure? Something wrong in the converter lube circuit of the Valvebody? The line pressure can't be so bad since the clutches and bands looked like new when inspected and it was driven hard! But something really is weird here...

Any ideas?