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#61
07-23-2025, 12:24 PM
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I ran the numbers through the diamondracing.net's calculator. I also looked up the CC of those 8-VR pistons.
Bore: 4.160 (40 over 400 bore) Stroke: 3.75 .020 deck clearance (typical for rebuilder pistons) 14CC dish for the 8VR pistons (per several online sources) 100CC for 6X-8 heads .039 gasket thickness Compression Ratio: 7.5:1. as it sits
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I could explain all this to the girl at the parts store, but she'd probably call the asylum. White '67 LeMans 407/TH350/Ford 3.89... RIP Red '67 LeMans. 407/TH400/Ford 3.25 |
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#62
07-23-2025, 04:08 PM
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Quote:
I measured my 8VR pistons at .039 in the hole on a stock (undecked) block. So CR would be even lower
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Frank M. 75 Firebird 68 Firebird 400 RAIII 66 Chevy II 461 Pontiac in AZ |
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#63
07-23-2025, 04:13 PM
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Mikael, did you verify by casting/date number that the block is from 1973, or is that what the previous owner told you. I would double check.
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Frank M. 75 Firebird 68 Firebird 400 RAIII 66 Chevy II 461 Pontiac in AZ |
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#64
07-24-2025, 02:29 AM
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As per the previous owner..
I will double check tomorrow |
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#65
07-24-2025, 11:20 AM
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I checked, and it's not from 73..
It's either from 74 og 75. The small number from the code ends with a 4 I think, but theres a big 75 besides the distributor hole. |
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#66
07-24-2025, 11:44 AM
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What is block casting number near bellhousing, behind passenger bank of cylinders? It will likely either be 481988 or 500557 cast into the rear of the block, facing upwards behind passenger bank.
__________________
I could explain all this to the girl at the parts store, but she'd probably call the asylum. White '67 LeMans 407/TH350/Ford 3.89... RIP Red '67 LeMans. 407/TH400/Ford 3.25 |
| The Following User Says Thank You to chiphead For This Useful Post: | ||
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#67
07-24-2025, 11:45 AM
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It says 481988
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| The Following User Says Thank You to Mikael Nielsen For This Useful Post: | ||
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#68
07-24-2025, 11:50 AM
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Good news, that's a thickwall block. Last of the good ones before the bean counters took 15-20lbs of cast iron out of the design.
__________________
I could explain all this to the girl at the parts store, but she'd probably call the asylum. White '67 LeMans 407/TH350/Ford 3.89... RIP Red '67 LeMans. 407/TH400/Ford 3.25 |
| The Following User Says Thank You to chiphead For This Useful Post: | ||
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#69
07-24-2025, 11:53 AM
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Thank god.
Finally some good news 😅 Thanks for the help! |
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