Intamin Tracks

Why do Intamin tracks switch to square to triangle? Just asking.

Depends on the amount of G force sustained on sections. More G's would mean it would switch to the square track, where less G's are sustained, you would only need the triangle track.

It's also how far apart they want to have the supports.
For example, on Millennium Force's lift and camel back hills, there is 4-tube track because tall supports cost a lot of money, and if they can spread out the supports and use less supports, then they save money. (Yes that was grammatically correct.) Millennium Force switches to triangular track when going through the tunnels and on the low section of track before the final turn.

Then at the opposite side of the spectrum, you have the Superman Ride of Steel Treo which all have 2-tube track for some forceful parts, but have loads of supports. They probably did this because the manufacturing of the intricate cross ties and extra tube bending was more money than having a bunch of supports.

This is the same reason that Intimidator 305 has a double spine. The supports are very far apart....not to mention the lift hill.

It also true about the forces, which is why Millennium Force has square track for its final over bank, even though it is low to the ground.

Same goes for strata coasters like Top Thrill Dragster. Look at how many forces must go into the up and down sides when its going at such high speeds. They have to build something that will support all of those forces without exploding... so to say.