Yes it is. The blocks are essentially the same.

 

 

If the LQ9 has a electronic throttle body with a returnless fuel system... just use the 4.8 intake, rails and throttle body. If the LQ9 comes with a ECM and it has the blue/green connectors... the ECM may not work unless it has the IAC chip soldered on the board, some do some don't. The IAC sensor is needed for the drive by cable throttle bodies. You should be able to use the 4.8's blue/red ECM but you'll need a tune especially If you're going cam, springs headers etc. you'll need injectors too. The duty cycle on the 24# injectors for the LQ9 are almost maxed out stock.

 

Cool, i was planning on using the 4.8 ECM and getting a custom tune. Any recommendations for the injectors?

 

Factory 8.1 injectors are 31 lb/hr and swap right in and the correct data can be pulled right from one of those files when it gets tuned. That's an option if you are more on a budget or you can get larger if you require them.

 

8.1 marine injectors are 42#.

 

For whatever reason I've noticed several people on the tuning forums having issues with the marine injectors. The data that people used was always off or they couldn't make them work.

 

 

I've had them in my truck without issue for 30K miles.