Not much lag when running a cammed 364ci LS1.
Single turbo...85% tuned he was making 730 RWHP.
My old Lunati cam was in that Trans Am years ago.
Single turbo > twins (At least in my opinion, don't really know how to explain it though)
TTi kit. TTi is the name of the place that makes the kit. Looks like twin turbo though.