firefighting1101

iTrader: (48)

what are the biggest valves that can go into 5.3 heads...i did some searching and could only find ls1/ls6 numbers...are they the same for 5.3's?

firefighting1101

iTrader: (48)

so i think it is 2.055 and 1.6 can anyone verify???

5.3LJimmy

iTrader: (10)

The valve spacing is identical on all gen 3 heads. So I would say what can fit in LS1/LS6 heads will also fit 5.3's. I have seen them with 2.04/1.6 and 2.055 isn't much bigger.

99mongooSS

iTrader: (4)

2.055 is the max, I think. most just go with the 2.04, ive heard it has a little less chance of valve shrouding on smaller bores (3.898-3.903) I wouldnt think you would have anything to worry about with a 3.905 though.

DONAIMIAN

iTrader: (18)

Ive seen 2.08s'

firefighting1101

iTrader: (48)

ok thanks for the info guys...i am going to be ordering some 2.055 and 1.6 valves this week i think...i know i am going to have to fly cut like crazy, but is there anything else i am giong to need to worry about...the guy putting my heads together in a genius with heads, unfortuneately ls1's are not his specialty...he typically does le mans cars...but at least i know the porting will be second to none and he said he will make them flow better than any other aftermarket casting