Is it possible to use a ls 4th gear as 5th gear in a b16 tranny?

The car is used for racing only and the rules are restrictive on hp and I need a shorter 5th gear. Rules also state it must be a oem gear ratio, thus trying to use a ls 4th as 5th gear.

Let me know what you think if it will work.

 

Nope.

 

It won't work. What type of racing are you doing? What top speed do you need in each gear?