took the stang out a few days back for some testing of the new combo, the strange thing that happened is when shifting from 1st to 2nd and 2nd to 3rd rpms drop from 6200 to about 4200-4300 rpm's . i know that sounds lke a lot of drop , but why is it doing so? could it be driving through the converter?

the car is a 92 mustang with 408 and an f2 blower , yank 4000 stall ( built for this engine,trans,gearing combo but on a slightly heavier car), th-400 , 3.55 gears, 28 inch slicks.

any thing i should check , or should i look into a new converter?

 

If the converter was intended for a heavier car the characteristics of the converter will be different in the lighter car

 

but would it cause the symptoms i'm having?

 

Well lower weight changes the stall characteristics so yes it could very well affect "shift extention " I would think

 

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