How to tell the stroke of your crank shaft?
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Joined: Jan 2006
Posts: 291
How to tell the stroke of your crank shaft?
In my previous thread i had a few questions well as always a few more came up summit racing wouldent help me without knowing my crank strok for my rod piston combo the current rods are 5.850 and the pistons are the off the shelf srp pistions for the 395? (thats what they say on there site ) now this all was sold to me as a kit for a 396 awile back and plans changed the pistons and rods are no longer adquite for what i need i need help finding my stroke so i can contiune building my bottom end thanks for the help. 
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From: Mooresville, NC
Re: How to tell the stroke of your crank shaft?
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Joined: Oct 2002
Posts: 2,931
From: Upstate NY
Re: How to tell the stroke of your crank shaft?
Originally Posted by JohnnyPappis
alright im confused with this formula someone help me out
http://www.mcmaster.com/
search for 2007A2. You can usually buy a similar one at Sears or Lowes. It's handy to have around. You can also mail order form McMaster-Carr.
If you added 7085A11, shown on the same page, it would make the job much easier.
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Posts: 291
Re: How to tell the stroke of your crank shaft?
Originally Posted by OldSStroker
What kind of measuring equipment do you have available? For the method I described you need a combination square. On the McMaster-Carr website:
http://www.mcmaster.com/
search for 2007A2. You can usually buy a similar one at Sears or Lowes. It's handy to have around. You can also mail order form McMaster-Carr.
If you added 7085A11, shown on the same page, it would make the job much easier.
http://www.mcmaster.com/
search for 2007A2. You can usually buy a similar one at Sears or Lowes. It's handy to have around. You can also mail order form McMaster-Carr.
If you added 7085A11, shown on the same page, it would make the job much easier.
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Joined: Oct 2002
Posts: 2,931
From: Upstate NY
Re: How to tell the stroke of your crank shaft?
Originally Posted by JohnnyPappis
hmmm ill hafta look into that other then that i might hafta take up the yard stick suggestion
us with the yardstick bit, right?
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From: Daytona FL.
Re: How to tell the stroke of your crank shaft?
Its a pain in the ***, but you could measure everything carefully, then figure it all out, or put the crank in the block, and a piston and rod , and measure again, top of block to lowest point of piston head, it will give you an idea, yuo aint gonna measure it in .001, just lookin for inches, or MM
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Re: How to tell the stroke of your crank shaft?
Originally Posted by OldSStroker
I assume you are us with the yardstick bit, right?
us with the yardstick bit, right?Of course and i think its a 3.875 stroke so what would the displacement be bored .30 with a stroke of 3.875 a 396 correct me if im wrong ? also what size rods should i use? the ones that came with it are 5.850 i want to get a new set of rods and pistons any suggestions?
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From: Upstate NY
Re: How to tell the stroke of your crank shaft?
Originally Posted by JohnnyPappis
Of course and i think its a 3.875 stroke so what would the displacement be bored .30 with a stroke of 3.875 a 396 correct me if im wrong ? also what size rods should i use? the ones that came with it are 5.850 i want to get a new set of rods and pistons any suggestions?
Boring a stock 4.000 +.030 ("thirty over") gives 4.030 bore and.....well you can do the math.
You really should have an engine designer/builder spec out your whole engine. All the parts have to work together to get the results you want or need. Building a 396 isn't just plug-n-play.
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Joined: Jan 2006
Posts: 291
Re: How to tell the stroke of your crank shaft?
Originally Posted by OldSStroker
Displacement = bore x bore x stroke x # cylinders x .7854
Boring a stock 4.000 +.030 ("thirty over") gives 4.030 bore and.....well you can do the math.
You really should have an engine designer/builder spec out your whole engine. All the parts have to work together to get the results you want or need. Building a 396 isn't just plug-n-play.
Boring a stock 4.000 +.030 ("thirty over") gives 4.030 bore and.....well you can do the math.
You really should have an engine designer/builder spec out your whole engine. All the parts have to work together to get the results you want or need. Building a 396 isn't just plug-n-play.
I understarstand that and im going to have an engine builder put it together but what good would it do if i dont do research and learn for myself what goes into this im honestly not dumb enough to think i can just slap this in there i just want to learn as much as can and make sure im getting the most i can out of this im enjoying the whole experience i am well aware of the amount of work that has to go into this i just weant educate myself....i see no harm in that
