LSx header/exhaust design for road/race car

[Omerta]

Just making decisions about exhaust design before making up the engine mounts.

It's a (road legal) race car being built for tarmac rally events here in NZ. Engine is currently making around 450hp. I'd like the exhaust I fit now to be capable of supporting up to 550/600.

4-1 short headers would fit the space available like this example (this is not my car, but also an LS into a Cerbera):



Would this be a reasonable design for a race application? I've read that 34" give or take is optimal so I'm thinking a bit longer than this with 1 3/4" primaries into 3" collectors.

From the collectors through to the back box, not sure if it will be 2 pipes with a X or H-pipe, or a single big pipe through to the back box. Are there power pros and cons or is it just a matter of going with what fits best and ensuring there's enough flow?

Making these decisions this week so appreciate any advice!

Don

Edited by Omerta on Thursday 11th September 01:22

[Omerta]

I know you're right about LS1tech, there is some great expertise there, but I find it hard to filter the good stuff from the homeboy bks. Having been here a while I feel know where the good advice comes from on PH (mostly), and I guess I'm looking for more of a trusted opinion so I know I'm at least in the right ballpark for the decisions I need to make.