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Are there any differences in Head Casting Numbers???

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Old Jul 5, 2003 | 05:28 AM
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Default Are there any differences in Head Casting Numbers???

If so, what are they? I keep seeing people reply to a cam only car that makes good power with "must be 241 heads" so I assume those flow better than others. Mine are like 863's I believe, but most my friends have 241's and yeah they walk me all the time, mod per mod!
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Old Jul 5, 2003 | 03:35 PM
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Default Re: Are there any differences in Head Casting Numbers???

c'mon, someone has to have some insight on this...

I think I maxed out the flow for my stock heads. Before cam, ran 11.43 @119 1.63. After cam (no it is not tuned yet and is running 11.9 or richer on the top) I ran an 11.6 @120 1.82. The 60' could have been better and the tower announcer said I was spinning into second gear, but the mph just isnt there, 4 runs none over 120mph. Thinking maybe the volume just can't get thru the heads???
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Old Jul 6, 2003 | 03:15 AM
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Default Re: Are there any differences in Head Casting Numbers???

The casting numbers are the last three numbers of the part number. A few are:

853 97-00 aluminum 5.7
241 01-03 aluminum 5.7
243 LS6 aluminum 5.7
852 and 706 99 and up 4.8-5.3 truck heads
873 99-00 LQ4 6.0 iron heads
317 01 and up LQ4 6.0 aluminum heads
035 02 and up LQ9 6.0 aluminum heads
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Old Jul 6, 2003 | 09:16 PM
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Default Re: Are there any differences in Head Casting Numbers???

Here's another one for you. My salvage yard motor possessed 4 rust-pitted intake valves. The shipper offered to replace them. He asked me for the casting number on the heads. I told him the number was 806. He had a difficult time locating the crossreference in his catalogue.
Turns out this LS1 was manufactured in July of 97.
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Old Jul 6, 2003 | 11:36 PM
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Default Re: Are there any differences in Head Casting Numbers???

OK, is there a difference in flow between the '853' and the '241'? I am just curious not that I am going to swap, but seems that these heads flow better, or something. Mod per mod my buddy is always a few mph more than me....drats!
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Old Jul 7, 2003 | 01:43 AM
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Default Re: Are there any differences in Head Casting Numbers???

241 are also found in some late model 2000 cars. I have them on my 2000 and they tend to make more power.
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Old Jul 7, 2003 | 03:56 PM
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Default Re: Are there any differences in Head Casting Numbers???

where are the numbers located on the head?
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Old Jul 8, 2003 | 03:31 AM
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Default Re: Are there any differences in Head Casting Numbers???

front outer corner of the head, on pass or drvrs side. Look at the flat portion at the laeding edge under valve cover area.
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