8.1 inch rod in stock block/stroke 350 and -----

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David Vizard
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Re: 8.1 inch rod in stock block/stroke 350 and -----

Post by David Vizard » Sat Sep 23, 2017 7:31 pm

gowest wrote:This is sounding like a dynamic flow bench !
No - you have only 300 guesses left.
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Re: 8.1 inch rod in stock block/stroke 350 and -----

Post by David Vizard » Sat Sep 23, 2017 7:39 pm

PackardV8 wrote:Interesting math; check me here, but an 8.1" rod and 1.74" of stroke = 9.84"; can't stay under a 9.025" OEM SBC block deck, so that's already .815" out of the deck before we consider the piston and rings?
EXACTLY RIGHT JACK BUT HOW WILL IT ALL WORK?????

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Re: 8.1 inch rod in stock block/stroke 350 and -----

Post by paulzig » Sat Sep 23, 2017 8:46 pm

Longer skirt on the piston, drop the rings down and the remaining .820" that pops up past the deck you'll shape to mirror the combustion chamber shape... ??

What are you making a diesel?

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Re: 8.1 inch rod in stock block/stroke 350 and -----

Post by David Vizard » Sat Sep 23, 2017 8:48 pm

paulzig wrote:Longer skirt on the piston, drop the rings down and the remaining .820" that pops up past the deck you'll shape to mirror the combustion chamber shape... ??

What are you making a diesel?
NO & NO
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Re: 8.1 inch rod in stock block/stroke 350 and -----

Post by travis » Sat Sep 23, 2017 9:09 pm

I'm guessing not a conventional cylinder head? Or some sort of spacer between the block and head? Otherwise I don't see it being physically possible. I haven't done the math but I don't think you could physically offset the pins far enough to fit this all together.

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Re: 8.1 inch rod in stock block/stroke 350 and -----

Post by David Vizard » Sat Sep 23, 2017 9:14 pm

travis wrote:I'm guessing not a conventional cylinder head? Or some sort of spacer between the block and head? Otherwise I don't see it being physically possible. I haven't done the math but I don't think you could physically offset the pins far enough to fit this all together.
Part right and part wrong but some good deductions all the same.
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Re: 8.1 inch rod in stock block/stroke 350 and -----

Post by cgarb » Sun Sep 24, 2017 12:12 am

This is going to sound weird, but are you making a compressor of some sort? I've heard of people using Volkswagen engines and having them run off 2 cylinders and compress air with the other 2.

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Re: 8.1 inch rod in stock block/stroke 350 and -----

Post by RCJ » Sun Sep 24, 2017 6:07 am

Wrist pin is offset to fit in to the deepest part of combustion chamber.

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Re: 8.1 inch rod in stock block/stroke 350 and -----

Post by John Wallace » Sun Sep 24, 2017 6:42 am

Using a conventional crank?

:?:
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Re: 8.1 inch rod in stock block/stroke 350 and -----

Post by ptuomov » Sun Sep 24, 2017 8:37 am

Sounds like some kind of spacer would be needed to move the crankshaft centerline down, unless the engine is destroked dramatically.
[b]Paradigms often shift without the clutch[/b] -- [url]https://www.youtube.com/watch?v=cxn-LxwsrnU[/url]

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Re: 8.1 inch rod in stock block/stroke 350 and -----

Post by David Vizard » Sun Sep 24, 2017 11:01 am

cgarb wrote:This is going to sound weird, but are you making a compressor of some sort? I've heard of people using Volkswagen engines and having them run off 2 cylinders and compress air with the other 2.
That is a great idea -wish I had thought of that when I could not afford the outrageous cost of compressors in 1970's UK.
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Re: 8.1 inch rod in stock block/stroke 350 and -----

Post by David Vizard » Sun Sep 24, 2017 11:02 am

ptuomov wrote:Sounds like some kind of spacer would be needed to move the crankshaft centerline down, unless the engine is destroked dramatically.
stock 350 stroke and crank location
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Re: 8.1 inch rod in stock block/stroke 350 and -----

Post by David Vizard » Sun Sep 24, 2017 11:02 am

John Wallace wrote:Using a conventional crank?

:?:
stock cast 350 crank
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Re: 8.1 inch rod in stock block/stroke 350 and -----

Post by ptuomov » Sun Sep 24, 2017 11:22 am

David Vizard wrote:
ptuomov wrote:Sounds like some kind of spacer would be needed to move the crankshaft centerline down, unless the engine is destroked dramatically.
stock 350 stroke and crank location DV
So is this a piston design with rings below the pin? The wrist pin would have to be inside the dome somehow and rings below the pin.
[b]Paradigms often shift without the clutch[/b] -- [url]https://www.youtube.com/watch?v=cxn-LxwsrnU[/url]

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Re: 8.1 inch rod in stock block/stroke 350 and -----

Post by David Vizard » Sun Sep 24, 2017 11:56 am

ptuomov wrote:
David Vizard wrote:
ptuomov wrote:Sounds like some kind of spacer would be needed to move the crankshaft centerline down, unless the engine is destroked dramatically.
stock 350 stroke and crank location DV
So is this a piston design with rings below the pin? The wrist pin would have to be inside the dome somehow and rings below the pin.
Well you and a couple of other posters are definetly moving in the right direction.

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