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Long connecting rods

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Cool53:
If you are doing a rebuild and your old connecting rods need to be rebuilt, and you need new pistons, AND your crank needs to be turned, consider buying a kit that offers a longer connecting rod than stock. Unless you are building a Mopar 440 or Hemi that already has rods that can reach the moon, then an engine like a small block Chevy likes to make more torque with a 6" rod as opposed to a 5.7" rod, you get a lot more bang for your money. The reason for this is that the piston stays stationary during the sweep longer and allows more pressure to build before the piston starts moving again, which gives it a lot more push. There is no downside to running a longer rod, except on some engines you may have a clearance problem. The longer rod makes cam tiing a lot less important, and if you draw a diagram of what happens with a longer rod you'll see why. If you have to buy parts, go for the better part. In this case they are not even that much more.
For those that load their own ammunition for shooting, you know how important the crimp is on the bullet. If the bullet sits loose in the case then when the primer is lit then the nitrocellulose starts to burn and almost immediately the bullet starts to move, and you end up burning a lot of the powder in the barrel. this causes a really slow bullet. But if the bullet is held as long as possible with a tight crimp then the whole charge is burned just as the bullet is released. More speed, more power. Instead of the powder fizzing it explodes. this all gets us to ignition timing. That's next.

themoose:
Jef

I agree with everything your saying but it begs the question of why didn't the factory engineers design the engine that way in the first place?

Moose

sixball:
Another plus for those of us who run the old inline engines i that longer(sometimes a lot longer) rods give us a choice of cheaper easier to find modern design pistons. One example is a guy who replaced 7" GMC rods in his 302 with 8" Hudson rods using Cjevy V8 4" bore pistons and saved 1.25 lbs per cylinder. The problem is the rods we need are expensive or not made.

Cool53:
We will be able to make rods affordable I would say, in the next year. And Moose, the factory ran the longest rods they could but didn't feel the shorter pistons needed would give enough support for longevity. Now with better alloys and lighter, thinner rings it is more possible.

sixball:
Some old race cars actually used welded rods when welding technology was not near what it is today. But neither was compression and RPMs.

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