I've got the front part of the exhaust on my scoob wrapped as it keeps the exhaust gasses hotter and the under bonnet temps down, hotter gasses flow quicker and cooler air going into the engine gives more power. Same can be applied to NA engines, best to keep it cooler under the bonnet. Also why induction kits with forced cold air work better.
Soak the wrap in water to make it easier to bend, fit to the manifold and secure with stainless steel ties/wire, bake it in the oven (while the wife is out!) at a low temp to dry it out and set the wrap, then give it a few light coats of high temp paint to keep the moisture out. I've got it on a cast section (the headers) and the up and down pipe and no problems with cracking.