05-11-2021, 01:49 PM | #1 |
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Location: Oak Harbor, WA
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1972 BB 402 question
Hey there. Opened up a new to me 402 last night. No ridge at all in the cylinder walls. The pistons are what appeared to be factory pistons, but what's with the hole in each one? Some had a 9 stamp, some had a 10 stamp.
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05-11-2021, 04:03 PM | #2 |
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Re: 1972 BB 402 question
Hole faces towards front of engine? Kinda big for a marker if so
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05-12-2021, 01:14 PM | #3 |
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Re: 1972 BB 402 question
I've seen locator pins in marine performance pistons but that hole doesn't "look" like one, just a drilled hole.
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05-12-2021, 02:06 PM | #4 | ||
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Re: 1972 BB 402 question
That is a bit big for a mark to orient the piston towards the front of the engine. Those don't look stock to me. What heads are on it? Stock? If memory serves me right, old school engine builders would do this to reduce the compression ratio just a bit.
Gary
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