Fixing to pull the trigger on a 408 short block. Thinking about cnc LS3 heads for it. Is there anything other than an intake manifold that I need to change? Will my headers bolt up to the new heads? Opinions on head choice??

Thanks!

 

You'll need rocker stands and 8 offset rocker arms for the LS3 heads. Headers and valve covers will bolt right up to those heads. Just make sure that if the 408 has valve reliefs in the pistons that the reliefs are large enough for the 2.16 intake valve.

Other than that, you're good to go. The LS3 heads are a great addition to a 408 and will make plenty of power with the right cam selection.

Mike

 

I ran that set up for a couple years and loved it. Everything Mikey stated is right except you will have to dremel or mill the passenger side valve cover out so the rockers don't hit. Other than that, you're good to go

 

Youll love LS3s on that 408z

 

What kind of power did you make on the 408 with LS3 heads?

 

Ooops, forgot about those pesky little dividers in the VC's.

Not a 408 but,,,, I self-ported a set of L92's and on my little 370 it put down 490/437 through a plastic L76 intake manifold. That was on a Mustang dyno, 9" rearend and full slicks (Z28).

Mike