Im going to be starting a 408 Stroker build soon and had a couple questions before I get too far into it, I'm going to be boring a lq4 block .030 over & I know the main things, what crank, pistons, and rods I need along with heads an all but what I don't know is:
1. All my accessories from my 5.3 should work for the front of 408 (lq4) block correct?

2. & will my 5.3 wiring harness hook up to the 408 and everything work without needing any additional wiring? Just didn't know if I would need a new wiring harness or not

- Thanks.

 

Is the 5.3 and the LQ4 both gen III motors? If so, you should be fine. You will need to get retuned of course.

 

Yes I believe they are. Just wanted to make sure I'd have all the wires I needee. & yes, tune is already planned.

 

What are your plans, Are you going NA?

 

Going with all forged internals. I have 243's for it right now but will probably go with different heads and cam, with a Holley intake. But I plan on spraying it quite a bit (at least a 200 shot)

 

FYI your power is in the heads and cam, so a big cube motor will require big heads to support it otherwise you have a big cube motor that makes same or less then some smaller cube motors make cause heads and cam sizing was off

 

Every thing will work the same on the LQ4. They are both ls engines. You will need someone to tune it before you start it especially if you change injectors.

 

I am starting a NA 408 as well, I have 317s for it but I am probably going to upgrade to some LS3s/L92 heads. I just need to figure out what the best route is for the intake. I will either spray or go turbo in the future so trying to figure out what CR I want to go with.

 

That's my biggest problem, trying to find the right Pistons and parts to get the CR where I want it so I can run pump gas

 

I think I am shooting for around 10.5, going with 68.5cc heads a thin head gasket and a 10cc dish, then if I decide to go boost I can get the heads milled and up the chamber to 72 cc and go with a thicker gasket and get down around 9.5 staying with the same pistons.