RagTop
Old Grumpy
I've got a 308 (302 .040 over) and a C4 with a shift kit installed. This setup has been in the car for many years. Today I took the vert out on some back roads and, when there was no traffic, stopped, manually shifted it into "1" and nailed the throttle. I watched the tach and when it hit 6 grand, I shifted to "2". The rpms dropped off to around 4,500 and I nailed it again. At around 5 grand it began acting like it was missing and at around 5,200 the tranny shifted itself into "D". I've run the car in the past at the local drag strip and never had this happen. What's going on? Is there something in the car's vacuum system that is causing the miss and the override shift? I did replace the vacuum modulator on the tranny some years ago, but I can't remember what I was trying to fix at the time. Vagaries of old age. Any suggestions on what could be causing this?