Can someone educate me about RODS??

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Apr 22, 2004 | 04:43 PM

Just Floor It

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From: Newport News, Va

Can someone educate me about RODS??

OK, I can tell you about anything involving a motor just about.....But I gotta few questions about Rods....

1) What are the advantages/disadvantages of steel rods/aluminum?
2) What is the deal with the rod sizes? Can someone talk about rod sizes??

Thanks

Apr 22, 2004 | 10:44 PM

onyxxtreme

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From: Locust Fork, AL

1. Stronger materials=less chance of breaking, lighter=less weight the motor has to rotate, meaning easier/quicker revving. I would go with a forged unit, as they are considerably stronger, being that the metal is "dense"
2. The longer the stroke, the shorter the rod you need. So if you went from a stock 3.622 stroke to a 4" crank, and used your stock rods, your pistons would fly out of the block. So you need a shorter rod to make the longer stroke work.

Apr 22, 2004 | 11:05 PM

DenzSS

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From: Kansas City, MO

You're a little off Onyx. When you go to a 4" stroke, you move the pin location on the piston, you don't go to a shorter rod. We went from the stock 6.098" rod to a 6.125" rod on my 4" stroke 408.

Apr 22, 2004 | 11:11 PM

pekkaz

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The longer the stroke the longer the rod should be in order to keep the rod angle and piston side loading acceptable. Usually piston pin is located closer to the top of the piston to make this or keeping stock length possible.

Longer rod in general makes the piston stay longer around top dead center area. This I believe favors high RPM power.

Apr 22, 2004 | 11:14 PM

DenzSS

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From: Kansas City, MO

There are a lot of benefits to a long rod when you get into the rotating assembly's acceleration curve as well.

Apr 23, 2004 | 12:16 AM

SSCamaro99_3

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From: Ballwin, MO

From what I've tried to understand, don't you want to run the longest rod possible without encroaching to far up the piston skirt, to the point that it affects the rings and durability of the pistons?