Kind of a new guy question but are Newhouse and Victor long spring trap parts interchangeable?

Not much is the same they have a lot of different designing in their build. I would guess a few springs might interchange but the parts in general won't match up much. You need parts post in the shed for the part and trap your looking for it might be easier.

Thank You Law Dog new to all this

No problem!

I’ve seen any number of Newhouse traps that have Victor springs on them. Presumably changed out by a trapper. Trap seems to function just fine with the replaced springs.

Due to the size of the spring holes in a Newhouse spring, the opposite is not true.

Other parts, like jaws and pans are not interchangeable.