Sorry if this question is noob, but what is it exactly? I know that it has something to do with making the auto shift harder, but what exactly is the mod?

 

Answered in the 4th gen FAQs.

And here's some reading material: http://forums.maxima.org/search.php?...der=descending

 

The concept behind the VB mod is to change the line pressure in your valve body. The VB regulates fluid pressure which in turn regulate how and when an Automatic transmission shifts.

If you slightly modify openings on the VB, more fluid will flow at a faste rate and change the way your car shifts. This is not a new mod, it has been done for years on many cars.

Two companies, Mobiltek in Texas and maximum Tuning on Long Island, NY are doing it for the Maxima's.

www.mobiletek.net/vb.html
www.howstuffworks.com

These two sites will definitely provide you with a lot more info on how auto trannys work and how the VB mod works.

Also, SEARCH is your friend.

Dave in York