Thread: 5.7 rods or 6.0?

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Can you run 6.0inch rods in a 350 without any modifications? What is the advantage with a 6' over a 5.7?

The dimension on the piston from the centerline of the wrist pin to the piston crown is called "compression height". To change from a 5.7" to a 6" rod without changing the rod throw on the crank, you must decrease the compression height by 0.300". That means not only buying new 6" rods, but also new pistons. In a paper written by Ron Iskendarian, he states that the horsepower return for this change will be negligible, on the order of 5 to 7 horsepower. If every other area of the motor has been optimized for maximum output and this is the only stumbling-block standing between you and a national record, it might be worth the investment. If this is for a run-of-the-mill street/strip motor, there are many other ways to spend your money more effectively.

If you were getting pistons anyway would this be something you would do? I read some of Smokey Yunicks book a while back and he seemed to emphasize a longer rod while still considering wrist pin location.

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JerseyRodder, I also remember reading Smokey's comments about longer rods, but other builders have shown that there is little to be gained. Here's the paper from Iskendarian. Scroll down a little more than halfway to:
Tech Tip 2005
Rod lengths/ratios
http://www.iskycams.com/techtips.html#2005