I have 2 sets of 317's and 1 set of 806's which one would be better for boost I have a 05 5.3l block I picked up that will be seeing around 12 to 15 psi the car will see more street racing than track also the car will be a daily driver thanks!

 

From what i under stand you have to do machine work to put 317s on a 5.3 because of the smaller bore but i cant remember 100%

 

No, you do not. It will lower your compression significantly though.

To the OP.
The 806 are the early LS1 heads with perimeter bolt valve covers. I wouldn't invest much in them.

With out knowing exactly what your building it would be hard to say for sure what to use. The biggest thing would be what compression ratio are you trying to achieve. Plenty of guys going fast on the factory 706/862 heads that come on the 4.8/5.3 engines.

Here is some of the factory head info https://www.performancetrucks.net/fo...g-info-434396/

 

Thanks brick i wasnt sure or not.

 

There is a guy in Phoenix running 317's on his turboed 5.3 in an ecsb. I can't think of his screen name right now but he is having good luck with his setup I think. If I remember right he was able to run a little more boost and timing given the lower compression. The issue to me would be out of boost performance, but depending on your right foot, you may be in boost more than you are out of boost

Edit: Found the guy that runs the 317's on his 5.3 however he does run flat top pistons which helps with his loss of compression a little. You might PM him to see how he likes his setup out of boost. Below are his specs........

 

Im currently running a 98 ls1,garrett 70mm, 80lb injectors,ls6 cam, PP96mm tb and intake on 10psi i picked up a 05 5.3L that had 706 heads on it but blew a head gasket so i was thinking about running the 5.3L on about 12-15psi i have 2 sets of 317's laying around thats why i asked tryon to get at least 600hp

 

317s would go very well on your build. Boost should be coming in very quickly so the compression loss shouldn't be a big deal. However, milling them .030 would be a great idea. Also you should consider a bigger cam. An isky 212 or 218 cam would wakeup your motor dramatically. A few members have also had great luck with the Speedinc TU1 cam in 5.3 turbo builds.

 

I run 317s, but they are milled. i had some milled to 65cc chambers, but hurt them. new set is milled .025 and i feel it will be a very good setup!

 

Where can I find that isky 212 or 218 cam.

 

Boost... pm stock48