Heads for F.I.
Heads for F.I. Going with 6.0 heads on a 5.3 motor with Radix and 9 psi. How much of a difference would it make with ported heads vs factory heads? Truck will also be getting a FMS F.I. cam and tuning.
TECH Junkie
Joined: Mar 2002
Posts: 3,019
Likes: 0
From: memphis tn
I don't think you'll see big gains with the 6.0 heads on a 5.3.The CR on a 5.3 is 9.5 to 1,your Radix setup with a decent tune and 93 octane works well with stock your stock CR and 7 to 9lbs of boost.With 6.0 heads your CR will drop to about 8.0 to 1,you will lose some power and some throttle response through the drop in compression that the supercharger will be hard pressed to make up.I've run a Radix for over a year and my past experience is that you don't see much if any gains after reaching 9.5 lbs of boost,you mostly generate heat after that point.I think you would see much better results by running a 6.0 engine at 9 to 9.5 lbs of boost.
TECH Junkie
Joined: Mar 2002
Posts: 3,019
Likes: 0
From: memphis tn
I'd go with a cam first then maybe port the heads.My Tahoe turned 13.20s with a stock cam and heads 5.3 at 5700lbs.With 9lbs of boost LT headers and a decent tune my RCSB should run in the mid to low 12s.
