Is it actually 5.7" length vs 6.0" length rods? Why would running longer rods be better if you are using pistons that correct the extra length? Wouldnt the longer rods be heavier and weaker? Are the longer rods only better to clear STROKER cranks (the weights)? Thanks ---

ps. sorry for the newb question, but I searched and couldnt find a question exactly like mine ---

 

http://web.camaross.com/forums/showt...ght=rod+length

http://web.camaross.com/forums/showt...ght=rod+length

Did you read those? I think it's mostly for stroker clearances, but there's a lot of theory behind it.

 

On some cranks you need more rod length to clear the counterweights, common in BBC stuff that is internally balanced. The big deal with the weight is that the piston will be smaller in a longer rod setup, so the total mass will go down because even though the rod gains a few grams the piston loses more than the rod gains.

Bret

 

Longer rods also travel further distance for the same amount of degrees, so the rod puts less side load on the up/down travel of the piston (since the distance is the same with the same crank, the longer rod travels less degrees. That puts less side load on the block wall). It's another theory that is suppose to free up all possible power.

The reason they make pistons to correct the extra .3" is so your piston does not hit your head. If your piston is already flat with the deck, and you add .3" to the stroke your piston is going to hit the head, and with a lot of force (short answer, it's bad). So if they have a piston that sits the wrist up .3" it now corrects for the extra .3" of the rod, and now the piston is still flat with the deck.

 

Ya can't tell the difference in either one.
If ya have the small weight dia size on your crank ya can use the 5.7. The compression height will be different making the 6.0 piston lighter.

Ya can't tell the difference on a dyno or in the car or longetivety.
The effect on the intake port is another book.

 

Longer rod makes a hair more tq. They also say it will help the life of the engine.

 

Before everyone goes spouting data of what rod length will do, just don't as dude said there is not much of a difference.

Bret