Registered User
go to your local GM dealer, ordered it on a monday came in tuesday. I use the crn-99893 springs with it aswell. with self ported heads and 58 mm tb and hooker longtubes , it dynoed 397/ 385 rwhp through a 9", until opti crapped out. I think its in the 420 range now after tuning a bit more on it , plan on going to dyno again and will post results