I am fairly happy with the way the car shifts but would like to switch to vacuum modulation to improve the downshifts. Is there any downside to installing a vacuum modulation kit without using a shift kit? Would I be wasting my time without doing the shift kit at the same time? Thanks.
-Josh

 

Police Interceptors have used them for years with & without the Shift kits. It will depend on which torque converter you have, as to how much the vacuum modulator will help. The smaller the diameter the torque converter, the better the gain.

 

Did you get my last P.M Dana?

 

Yes..

 

Thanks Pro Built. I am actually planning to give you a call on Monday. I currently have a TCI 4000 with a 2.2 STR. I believe it is a 9" converter.