Like the title says are they different?

 

the only distinction I know of is convertible and regular models being different

 

No they are not different and this is not an engine tech question.

 

The fuel lines are routed differently on the LS1 cars. That's why Spohn only made an LS1 SFC for a while.... it interfered with the fuel lines for the LT1 cars. He eventually modified the design so it would fit both cars.