55.2-59 58 SWB + C4 + LS1 - Header Help

[QBRacing]

OK. Getting closer to finalising the engine bits an just wondering what the LSx conversion people are running for headers when the use a C4 Corvette setup like the flatout engineering kit.

I tried the factory cast headers I have from the Holden I got the engine from and they just touch the bolts on the rear upper arms by the exit of the exhaust ports for #3 and #4 cylinders .... If only they were steel and I would have just massaged them slightly. (refer my attachments)

Next has anyone heard of or used speed-engineering. He has a couple of sets of conversion headers which look like they should work (1021 and 1029) but before I commit I'm thinking why not ask as someone bound to have played with this before.

Q