Cadillac CTS-V - cts-v exhaust manifolds v1 vs lsa

is there any physical difference between the these manifolds?

v1 casting numbers 12578029 12578030

lsa casting numbers 12611322 12611324

Anyone?

Is the exhaust port different?

I found a few vague references to the lsa manifolds being tighter to block but really do not want to buy another set just to find out they are the same as the ones I have.

They look the same to me.

I'd be interested in anything you find out. I have a friend with an LS2 C6, he put LS7 manifolds and exhaust on it and it really woke things up. Since then I have wondered if LSA manifolds were internally larger and would bolt up to the stock V1 cat-back for a similar improvement without the downsides of headers.

i would think that the ports would be larger due to the bigger cubes. but i dont know..

aurora: what downsides are there to headers? out side of removing them they are the best bolt on you can get

aurora: what downsides are there to headers? out side of removing them they are the best bolt on you can get
Plenty of people have clearance issues, with wires burning on them, or the steering shaft clunking. Plus in many states you are unlikely to pass a visual inspection with them. And they are pricey with cats, and louder.

Headers are a good mod, but I don't want them on my Caddy. I'm sure I'm not the only one.