5.3L head question
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i have an 2000 LS1 trans am, i recently picked up an 04 sierra with a 5.3L that has after market heads on it, well the guy gave me the stock 5.3L heads, casting is 862, with it and they also have comp .600 lift beehive springs in them.
well what i was wondering by reading on some pages and lookin around, if i sent these out and got them ported and polished (maybe valves depending on $$) to flow better, then put them on using cosmetic .40 head gasket.
should put me around 11-11.5:1 comp ratio using the chart below with some rough estimation on what the head gasket will give me
questions i had were..
if i did this would it be worth the time, effort and money?
would i be able to run 93 pump gas with out a problem? if not should i use stock gasket size then? if so would it still be worth it?
could i get even smaller gasket size, or get them milled for higher CR and still be good on 93 octane?
thanks!
9.1:1 = 77.27
9.2:1 = 76.21
9.3:1 = 75.16
9.4:1 = 74.15
9.5:1 = 73.16
9.6:1 = 72.19
9.7:1 = 71.24 (Approximate Combustion chamber of 6.0L heads +/-)
9.8:1 = 70.32
9.9:1 = 69.41
10.0:1 = 68.53
10.1:1 = 67.66
10.2:1 = 66.67 (Stock LS1 Head)
10.3:1 = 65.96
10.4:1 = 65.18
10.5:1 = 64.45 (Stock LS6 Head)
10.6:1 = 63.61
10.7:1 = 62.85
10.8:1 = 62.10
10.9:1 = 61.37 (Approximate Combustion chamber of 5.3L heads +/-)
11.0:1 = 60.66
11.1:1 = 59.96
11.2:1 = 59.27
11.3:1 = 58.60
11.4:1 = 57.93
11.5:1 = 57.28
11.6:1 = 56.65
11.7:1 = 56.02
11.8:1 = 55.41
11.9:1 = 54.81
12.0:1 = 54.20
well what i was wondering by reading on some pages and lookin around, if i sent these out and got them ported and polished (maybe valves depending on $$) to flow better, then put them on using cosmetic .40 head gasket.
should put me around 11-11.5:1 comp ratio using the chart below with some rough estimation on what the head gasket will give me
questions i had were..
if i did this would it be worth the time, effort and money?
would i be able to run 93 pump gas with out a problem? if not should i use stock gasket size then? if so would it still be worth it?
could i get even smaller gasket size, or get them milled for higher CR and still be good on 93 octane?
thanks!
9.1:1 = 77.27
9.2:1 = 76.21
9.3:1 = 75.16
9.4:1 = 74.15
9.5:1 = 73.16
9.6:1 = 72.19
9.7:1 = 71.24 (Approximate Combustion chamber of 6.0L heads +/-)
9.8:1 = 70.32
9.9:1 = 69.41
10.0:1 = 68.53
10.1:1 = 67.66
10.2:1 = 66.67 (Stock LS1 Head)
10.3:1 = 65.96
10.4:1 = 65.18
10.5:1 = 64.45 (Stock LS6 Head)
10.6:1 = 63.61
10.7:1 = 62.85
10.8:1 = 62.10
10.9:1 = 61.37 (Approximate Combustion chamber of 5.3L heads +/-)
11.0:1 = 60.66
11.1:1 = 59.96
11.2:1 = 59.27
11.3:1 = 58.60
11.4:1 = 57.93
11.5:1 = 57.28
11.6:1 = 56.65
11.7:1 = 56.02
11.8:1 = 55.41
11.9:1 = 54.81
12.0:1 = 54.20