Chromoly Vs Mild Steel K Member

Also keep in mind that it is harder to weld the 4130 than the mild steel.

Chromoly vs mild steel k member.

A sfi 25 5 cage can be either mild steel or chromoly however a 25 2 cage must be chromoly only. Crome molly chromemoly has a higher ultimate strength so it is much harder and a mild steel cage will fail before it does. A 25 5 cage will cert a car to run 7 50 or slower at a max weight of 3600 pounds. 4130 alloy steel.

The chromium adds strength hardenability and a level of corrosion resistance to mild carbon steel though chromoly is not as corrosion resistant as stainless steel. 4130 alloy steel carbon steel vs. Some are stronger then others but some you are going to pay out the ass for. A 25 2 cage will cert a car to run 6 0 and slower at 3200 pounds max.

Ths tress relieving part is bogus. This kit was designed for the abuse of hardcore drag race road race and street enthusiasts. I did not understand either as i came from drag racing but that is what the ot sanctioning bodies require. I am cheap so upr was the one for me they have had their problems in the past but the k members have been redesigned and are much better.

Drag racers benefit more from using chromoly because they can use a thinner wall steel over mild. Cage mild steel vs. Use er70s wire and you won t need to passivate the welds since the wire is ductile. But the fact is someone has had a problem with all brands steel or chromoly.

There are going to be people saying chromoly will crack or i have this friend that blah blah blah. Upr s all new chrome moly k member will save more weight and exceed any strength limitations of mild steel while allowing maximum header and oil pan clearance.