G'day and welcome.
A few thoughts - At the very least you should do a retune. Your rayd tune accounts for the cam, so running it without the cam may be an issue. Rayd may be able to take the existing tune and adjust it to minimise cost but I'm definately not seeing an OTS tune or running the custom tune without the cam as being safe.
I'd get in contact with rayd and ask his advice what the minimum cost option is going forward is. By the sound of it, an adjusted tune to account for the OEM cam would be the way to go...even if you get the cam installed straight away a retune is advisable.
Cheers, hope you have a relatively painless swap.
If you keep the OEM intake and turbo then a Stage 1+ OTS tune is about aggressive as you can go and probably be safe. Even that is taking some risk. OTS tunes aren't a good idea with significant mod sets.
If you've got the OEM parts for airbox, turbo and downpipe I would use them and bring it back to life on an OEM tune, then investigate getting it back to the spec you want
James
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