TTI headers which ones to use?

Not great. It's like a 90° sharp turn. Sure it's pretty restrictive, but not as bad as the stock manifold, I'm sure!

Thank for getting back to me.
The last headpipe I saw, looked like the pee-trap under a kitchen sink.
A tight 120* bend trying to get the pipe over the steering.
Did you need to get a muffler shop etc, to form the pipe ?
Would you be so kind as to send us a pic.
Thanks again.