OK guys, I'm looking for some 4th gen owners here to fill me in on some LS1 specs. Preferably only stock or mild bolt-ons here, please! So, I'm thinking of retro-fitting an LS1 into my truck (as opposed to my 383, which I may put to good use as a super-street motor) because of the EFI and power. NOW, I'm wanting to know... Have any of you guys ever had a dyno on your LS1? I want to know ACTUAL power rating, not the conservative 325 horsesGM gave it. I'm willing to change the intake and put headers on there, headers were planned on anyway. Input please?
Also, I would be getting all of it, including the tranny. My truck weighs 3300lbs, which I believe is close to a 4th gen, so how about economy guys? It's a DD truck and if I was getting more than 20mpg I would be a happy camper. Specter, Stig?