Which is stronger 5140 forged pistons or 4310?

[chuddleston2003]

Hey guys and gals I just recently bought an eaton from a member on another forum and looking to forge my engine, just wondering which is stronger the 5140 or 4310? My hp goal is 6-700 hp and I know I will need to upgrade the blower just getting into superchargers now. New to the supercharger stuff. All help and comments are welcome, I will be upgrading the fuel and injectors and all that stuff.

 

[white95]

This is an excerpt from a magazine article about crankshafts but contains the information you seek about metallurgy.

The most basic aftermarket-grade steel is 5140, which boasts a tensile strength of about 115,000 psi. This material used to be-and to some extent still is-an excellent choice for racers on a budget, but is less common than in years past due to the increasing affordability of premium alloy cranks. These include 4130 and 4340 forgings, which have tensile strength ratings of approximately 125,000 psi and 145,000 psi, respectively. Engine builders and crankshaft manufacturers universally accept 4340 as the ideal alloy for strength and durability.

http://www.hotrod.com/how-to/engine/0710phr-crankshaft-tech/

The pistons in my stroker are 4032 aluminum and piston/rods are 4340. The kit was rated for about 750 HP for example.

 

[Pete@FTR]

Have a look here if you're interested in the metallurgy: http://www.makeitfrom.com/compare/S...40-SCr440-1.7035-41Cr4-G51400-Chromium-Steel/

Your best course of action is to call the manufacturer- they have all of the data on the different materials and how they relate to their products specifically.

 

[95opal]

4340 is what you want.

 

[96blak54]

Either piston will be fine. Just go along with whats in your price range.

 

[BLWNBYU]

Wut.... Your pistons aren't steel...

2618 Aluminum is what you want..

 

[Nighttrain]

4340 is what you want. I deal with metalurgy all day. Its the ideal alloy available right now at a good price because of not only tensile strength but heat extraction. Someone else up above suggested aluminum. For a block and heads maybe because of cooling passages and oil galleries and weight savings its ok. As a piston and rods? No way, itll melt down and bend. I will say aluminum alloys have come along way but for your rotating assembly, no way. Steel alloys is cheaper and more reliable