2000WS6TA

iTrader: (5)

im going to be buying the PRC stage2.5 5.3L heads and i want the final compression to be about 11.5:1 i think ive determined that it will take about .030 milling to reach 11.5:1. could someone confirm this for me? also im getting the TSP228R 228/228 .588/.588. now will this run into clearance issues or is the lift small enough that i wont have any issues? i think it will be fine but id like some conformation for a some peac of mind. thanks.

GuitsBoy

iTrader: (4)

What block, what gasket, and what was the original combustion chamber size of the heads?

2000WS6TA

iTrader: (5)

stock block, stock gasket and im pretty sure the original combustion chamber is 61.15

PREDATOR-Z

PRC 5.3L Stage 2.5 are 63/64 cc
To reach ~ 11.5 you'll need ~ 59 cc which will yield ~ 9.0x:1 DCR (too much)

I would mill only .010 for a 62 cc

2000WS6TA

iTrader: (5)

what about for 61cc. still to much or should be safe?

PREDATOR-Z

Do you want to run premium? then 61cc would be Ok. That is .015 mill.
But first measure chamber with a burette and mill from there.

2000WS6TA

iTrader: (5)

i never put anything but premium gas in my car. never had anything but 93 octane in it. so thats no problem. and i dont know what a burette is or where to get one, but what would the reasoning for measuring first?

PREDATOR-Z

So you know what are the exact chamber measurements first and then decide how much to mill. On average it is .005 flat mill for every 1 cc.

2000WS6TA

iTrader: (5)

oh ok. thanks alot. ill just ask my mechanic what he thinks and go from there... you wouldnt happen to know the max lift these heads will take without having to flycut? and with the .015 milling does that just take .015 away from the max lift you can have?