View Full Version : Which Heads?


mean05 5.3
10-17-2006, 02:33 PM
i will be putting some heads on my truck pretty soon, but don't know which ones i want to get so i am looking for advice, a list of my mods are in my sig and remember that early next year i will be putting a 6.0 in it so i am more looking for something that will match up good with that, from what i ahev seen either some LS6 heads or Patriot would be the way to go.
Thanks
Virgil

mean05 5.3
10-18-2006, 12:23 PM
no thoughts or suggestions??

airdeano
10-19-2006, 12:02 AM
the prob with the 5.3 is the small combustion chambers.
if you use OE style heads from a LSx engine flow will be great,
but the larger combustion chambers will lower the compression and
power. so the trade-off sucks.
milling the 5.3 03-06" will substantially raise the CR .5-.75
which your cam is looking for COMPRESSION.
the smaller bore is ok, but the ratio for flow will poop out
before the raised flow rate is needed.
id find some core 5.3 heads, mill 'em, port 'em (280ish) will
probably be the best flow. a bigger valve is helpful in flowrate
but again the small bore will hold that as the walls will shroud
20% of the flow.
the LSx guys love the 5.3 with larger valve and unshroud the
valve heads to accomodate the 3.905 bore. 2.02-2.08 normal
the 3.780 bore is just small...

airdeano