The new Lightning headers are stainless inside tubes and regular steel outer tubes.

i looked at the lightnings,, but the full stainless ones are not that much different in price than the cmi's. those welded together pieces just look like a future failure point to me.

The KE Headers flow equal to about a 2" primary. The primary size needed and runner length needed for a motor is dependent upon a lot of factors such as exhaust port design, cam profile, and compression, but at a certain HP level you just need to get some flow.

If I had a NA motor, the KE would be my #1 choice as it is a 2" primary with a 4-2-1 collector and a full 32" equal runner.

That being said, we ran our KE headers to a solid 1500hp on a supercharged application, but I wouldn't recommend it. 800-1100hp blower motor is a toss up on that or stainless marine. Big HP blower motors I would go with Stainless marine for more flow.