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

General engine tech -- Drag Racing to Circle Track

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Joe-71
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Re: 8.1 inch rod in stock block/stroke 350 and -----

Post by Joe-71 » Sun Sep 24, 2017 1:11 pm

2.500" spacers on block with 8 new tall sleeves. O ring block to spacers. Joe-71

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

Post by ptuomov » Sun Sep 24, 2017 1:13 pm

David Vizard wrote:
ptuomov wrote:
David Vizard wrote: 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.DV
I thought about doing the piston wrist pin bore with caps that are fastened with bolts. Like main caps. That would be heavy, though, but would allow no wrist pin bore openings into the combustion chamber. Then the rings could come high up like in a modern piston, right up to top of the bore.
[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 4:18 pm

Guys,

I had little idea the opening posts shot of a long rod was going to cause so much response and interest.

I am off 'down under' to do a seminar in Sydney tomorrow (Mon 25th Sept). I am excited about this one as due to the interest the last one in 2015 caused. I am getting a number of the chief engine development engineers from top teams attending.

Anyway due to this busy trip I won't have time to put up any posts so you will all have to fight among yourselves until after the 5th of Oct.


DV
David Vizard Small Group Performance Seminars - held about every 4 weeks. My shop or your shop. Contact seminar organizer at marvingvx@gmail.com for details.

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

Post by RevTheory » Sun Sep 24, 2017 4:27 pm

We'll keep the octagon bloody until you get back, lol.

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

Post by sanfordandson » Sun Sep 24, 2017 4:31 pm

Move the crank down? :shock:

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

Post by CGT » Sun Sep 24, 2017 6:54 pm

David Vizard wrote:I am getting a number of the chief engine development engineers from top teams attending.
Top teams?

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

Post by gvx » Sun Sep 24, 2017 7:33 pm

sanfordandson wrote:Move the crank down? :shock:
Hmmm.. what could be the purpose in extending the crankshaft lower in the block geometry? Interesting thought.
3 DAY SEMINAR. Instructor DAVID VIZARD. Pleased to announce for our next seminar has been sceduled Jan 12, 13, 14 location Mt Holley NC near Charlotte for information go to ->http://www.davidvizardperformanceseminars.com

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

Post by cjperformance » Sun Sep 24, 2017 8:42 pm

He has already said stock stroke and crank location in stock deck 350 SBC and no head gasket, has indicated an abnormal CR ratio but not wether that is high or low.
Maybe this is a cooky 2 stroke build with long closed end smaller diameter cylinder sleeves with ports for intake and exhaust,, lol.
Craig.

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

Post by fdicrasto » Sun Sep 24, 2017 9:46 pm

2 piece piston to capture the pin.

Mark O'Neal
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Re: 8.1 inch rod in stock block/stroke 350 and -----

Post by Mark O'Neal » Mon Sep 25, 2017 3:21 am

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?
The ring stack is irrelevant to the C/H.

He just has to fit the rings, lands, and half the pins into a -.815 C/H

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

Post by Mark O'Neal » Mon Sep 25, 2017 3:23 am

Counterbore the head, and build a piston with a 1.000 top land...... :P

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

Post by kimosabi » Mon Sep 25, 2017 9:29 am

F1 style piston with a short pin.

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

Post by ptuomov » Mon Sep 25, 2017 9:31 am

kimosabi wrote:F1 style piston with a short pin.
F1 has that kind of negative compression height such that the wrist pin is out of the bore?
[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 kimosabi » Mon Sep 25, 2017 10:00 am

ptuomov wrote:
kimosabi wrote:F1 style piston with a short pin.
F1 has that kind of negative compression height such that the wrist pin is out of the bore?
Not that much but the pin sits just below the deck. I'm sensing offset pin and offset grind on the crank here too as well as a smaller pin. That pin has to be installed somehow either way.

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

Post by ptuomov » Mon Sep 25, 2017 10:11 am

kimosabi wrote:
ptuomov wrote:
kimosabi wrote:F1 style piston with a short pin.
F1 has that kind of negative compression height such that the wrist pin is out of the bore?
Not that much but the pin sits just below the deck. I'm sensing offset pin and offset grind on the crank here too as well as a smaller pin. That pin has to be installed somehow either way.
He just said stock stroke, stock crank location. There's no way to get the pin below the deck, I believe. The next logical question is how to get the pin inside the dome. I wouldn't want to expose the pin and the locks to the combustion chamber, not even with buttons on holes. I think multi-piece piston with some sort of bolted-on cap or caps is the most likely plan for these rods. Since the main reason that I see for doing all that is to reduce the piston weight for large dome piston (like in a hemi chamber), I don't see it really working out in net given the weight and complexity of a multi-piece piston.
[b]Paradigms often shift without the clutch[/b] -- [url]https://www.youtube.com/watch?v=cxn-LxwsrnU[/url]

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