SS/GT LS with a carb?
 

Is it possible to run a carbureted LS in a GT class? Also, if I wanted to claim an 07 ls4 (5.3) I assume I could use any 5.3 block I wanted regardless of iron or aluminum? I say this because an iron aftermarket block is listed as acceptable for a replacement block even though an ls4 is aluminum.

Re: SS/GT LS with a carb?
 

As far as I know replacing injection with a carb in SS or SS/GT is only allowed in the Modified classes. Better be looking at NHRA.com on the legal issue of the block or send NHRA (Wesley, Dave or Pat) an Email to be safe and sure.
This is the heading on the NHRA rules that must be followed. If you don't find it in SS or SS/GT section it is not legal.
Remember the NHRA rule book is written as a "Stack" one class following the rules of another/previous with exceptions or additions.
SECTION 12B
SUPER STOCK/GT
Requirements and specifications for GT classes
are the same as those for Super Stock classes -
Section 12A - with the following exceptions:

Re: SS/GT LS with a carb?
 

Several years ago I had messaged Bob Blackwell when he was still involved and he had told me then that an iron block was allowed to be used with that combination. Don't know if that would have changed at all by now.
Carb is a definite no.

Rick