Water holes
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Drifting
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From: Wisconsin
2024 C3 of the Year Finalist- Modified
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Water holes
As you can see 6 water holes
These have been modified, what's the purpose or benefits?
Last edited by Mdbirk; Jan 28, 2023 at 12:07 PM.
Is my vette stock?? HAHA
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From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
Force the water to the back of the block for better cooling....maybe. If it was used for racing, they tried many different things, they used to fill the bottom of the block with cement to keep it from twisting, expanding or letting the rods out...
Le Mans Master
Joined: Aug 2017
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From: Cool Northern Michigan
The smaller photo appears to be World Products Merlin new design block with maybe a 4.125 bore? I see its worth around $3200, just the bare block.
Evidently, GM thought it wasn't necessary to bore additional cooling holes in their early block, big photo.
Can't see any numbers on those pistons. Is that a 454? Maybe 30 over?
You can see how the big blocks got its name "porcupine head" the way the pushrods are off center, staggered, poking all different directions.
The screens in the lifter valley were to keep debrie from entering the oil pan. In some rare cases, a clip would break off from the hyd lifter and drop down into the oil pickup sump screen. A solution or precaution was to epoxy aluminum screens over the drain-back holes. Myself, I would worry more about the screens coming loose than a lifter clip.
The small, drilled hole on the piston top I believe forces compressed gases into the ring land thereby forcing the top ring outward = better seal. IDK
Some racing pistons have a series of real small holes drilled around the perimeter to do just that, force the ring against the wall.
I have never seen GM do that on a BBC.
Note how the upper cylinder has machined clearance for the huge valve heads to enter.
Evidently, GM thought it wasn't necessary to bore additional cooling holes in their early block, big photo.
Can't see any numbers on those pistons. Is that a 454? Maybe 30 over?
You can see how the big blocks got its name "porcupine head" the way the pushrods are off center, staggered, poking all different directions.
The screens in the lifter valley were to keep debrie from entering the oil pan. In some rare cases, a clip would break off from the hyd lifter and drop down into the oil pickup sump screen. A solution or precaution was to epoxy aluminum screens over the drain-back holes. Myself, I would worry more about the screens coming loose than a lifter clip.
The small, drilled hole on the piston top I believe forces compressed gases into the ring land thereby forcing the top ring outward = better seal. IDK
Some racing pistons have a series of real small holes drilled around the perimeter to do just that, force the ring against the wall.
I have never seen GM do that on a BBC.
Note how the upper cylinder has machined clearance for the huge valve heads to enter.
Thread Starter
Drifting
Joined: Jul 2022
Posts: 1,359
Likes: 822
From: Wisconsin
2024 C3 of the Year Finalist- Modified
2023 C3 of the Year Finalist - Modified
2022 C3 of the Year Finalist - Modified
The smaller photo appears to be World Products Merlin new design block with maybe a 4.125 bore? I see its worth around $3200, just the bare block.
Evidently, GM thought it wasn't necessary to bore additional cooling holes in their early block, big photo.
Can't see any numbers on those pistons. Is that a 454? Maybe 30 over?
You can see how the big blocks got its name "porcupine head" the way the pushrods are off center, staggered, poking all different directions.
The screens in the lifter valley were to keep debrie from entering the oil pan. In some rare cases, a clip would break off from the hyd lifter and drop down into the oil pickup sump screen. A solution or precaution was to epoxy aluminum screens over the drain-back holes. Myself, I would worry more about the screens coming loose than a lifter clip.
The small, drilled hole on the piston top I believe forces compressed gases into the ring land thereby forcing the top ring outward = better seal. IDK
Some racing pistons have a series of real small holes drilled around the perimeter to do just that, force the ring against the wall.
I have never seen GM do that on a BBC.
Note how the upper cylinder has machined clearance for the huge valve heads to enter.
Evidently, GM thought it wasn't necessary to bore additional cooling holes in their early block, big photo.
Can't see any numbers on those pistons. Is that a 454? Maybe 30 over?
You can see how the big blocks got its name "porcupine head" the way the pushrods are off center, staggered, poking all different directions.
The screens in the lifter valley were to keep debrie from entering the oil pan. In some rare cases, a clip would break off from the hyd lifter and drop down into the oil pickup sump screen. A solution or precaution was to epoxy aluminum screens over the drain-back holes. Myself, I would worry more about the screens coming loose than a lifter clip.
The small, drilled hole on the piston top I believe forces compressed gases into the ring land thereby forcing the top ring outward = better seal. IDK
Some racing pistons have a series of real small holes drilled around the perimeter to do just that, force the ring against the wall.
I have never seen GM do that on a BBC.
Note how the upper cylinder has machined clearance for the huge valve heads to enter.
