I am doin a 5.3 s-10 build and have been researching this site and ls1tech heavily over the last few weeks and have changed my mind several times, I have pretty much settled on the 317 heads at this time because I have found some good deals on them. this is a budget 1/8th mile drag build that will have a cam and stall. Stock bottom end 5.3. My question is how much have you guys gotten away with milling these heads and running a good sized cam? I am thinking of going with the TR 220 cam??? Subject to change though. I have read over how to measure ptv several times but I just cant get it so Im hittin you guys up for any help, I really dont wanna flycut but if I have to do it to get a CR I will.
Any advice appreciated.

 

The 317s will be a dog on a 5.3. Even with a mill the compression will just be too low.

 

Do NOT use 317's on a 5.3 unless you are running boost over 15 psi. The compression will be around 8.5:1. Some 243's would be better if you shave them down. 243's and 317's are essentially the same head, just different size chambers. What cam are you thinking of?

 

Tr220 is a good proven can in a 5.3, just run around a 32-3600 rpm converter with it.

 

^^Good advice there.

317s are 72-74cc chambers
243s are 64cc chambers

317s have solid valves
243s have sodium-filled valves (if from a z06)

everything else is the same.

 

pickup a set of 706/862 5.3 heads mill them .040 and do a valve job
These heads are cheap!
Leave those 317s alone thats no good for your setup