I have some jets form my old set up off my lt1. I now have the kit on my ls1 just wanted to know if I can use the same jets or not.

 

if you are using the same kit the jets themselves will work but due to having different fuel pressure between the 2 cars you will need to change the fuel jet size for each HP level.

Example:
NX Single Nozzle Jetting
LT1 (45psi fuel pressure) LS1 (60psi fuel pressure)
100hp 52n 31f...............52n 28f