what is the difference between rod lengths?
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From: Merrillville,In (chicago)
what is the difference between rod lengths? ok, i understand it is the length of the rod...but is there anything gained or lost by using a 6.125 instead of a 6.098?
why do they make pistons to accommodate both?
the reason i ask is because i have forged pistons that are going into a forged 347 i am building and i need 6.125 so the question popped in my head.
Thanks
Louie
why do they make pistons to accommodate both?
the reason i ask is because i have forged pistons that are going into a forged 347 i am building and i need 6.125 so the question popped in my head.
Thanks
Louie
There was a discussion on this a while back. I wish I could remember exactly what the reasoning was, but I believe the shorter rod is the best route. I forget why though. Try doing a search in the advanced section.
I have allways been told the longer rod you can get in there the better. The longer rod will allow the piston to dwell at TDC slightly longer allowing more air/fuel to be pulled into the chamber. This action also is supposed to put less stress on the cylender walls and the rod/piston itself.
This is what I have been told years ago, does it hold water?
This is what I have been told years ago, does it hold water?
The longer rod you can get in the better mostly, there are always exceptions though. The major benefit to a long rod is that it keeps piston speed lower compared to a short rod at the same time. I also forgot to mention there is less side loading on the rod with a longer rod, Jeremiah touched on that slightly.
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i always believed that the longer rod did make the piston dwell at tdc for a degree or two at most i believe. But not to pull in air/fuel mixture but the combustion pressure will be slightly higher before the piston is pushed back down on power stroke thus creating some more HP. just what i believe. but rod length is something that should be considered in the whole package of what you want to do with this engine.
just my two cents
Ryan
just my two cents
Ryan
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Take a look at this:
http://victorylibrary.com/mopar/rod-tech-c.htm
It tells you a lot on the rod length subject.
I would rather use a shorter rod, if that is what it take to make room for the piston rings, oil ring in particular.
I am talking street DD aplication here.
Br//
http://victorylibrary.com/mopar/rod-tech-c.htm
It tells you a lot on the rod length subject.
I would rather use a shorter rod, if that is what it take to make room for the piston rings, oil ring in particular.
I am talking street DD aplication here.
Br//
