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.

Chromoly vs mild steel k member.

But the fact is someone has had a problem with all brands steel or chromoly. Use er70s wire and you won t need to passivate the welds since the wire is ductile. 4130 alloy steel carbon steel vs. Cage mild steel vs.

There are going to be people saying chromoly will crack or i have this friend that blah blah blah. 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. A 25 2 cage will cert a car to run 6 0 and slower at 3200 pounds max. Some are stronger then others but some you are going to pay out the ass for.

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. Drag racers benefit more from using chromoly because they can use a thinner wall steel over mild. 4130 alloy steel. This kit was designed for the abuse of hardcore drag race road race and street enthusiasts.

A 25 5 cage will cert a car to run 7 50 or slower at a max weight of 3600 pounds. In nasa we have to use the same gauge whether it is mild or chromoly so the benefit of light weight is not as great. Ths tress relieving part is bogus. Also keep in mind that it is harder to weld the 4130 than the mild steel.

When racecars were just beginning to be made from chrome moly there were brittle failures caused by the lack of heat treating and stress relieving. I did not understand either as i came from drag racing but that is what the ot sanctioning bodies require.