I have the 275 hp version LT1. It has headers and cold air intake, which should put it a couple hp away from 300. The motor has a knock in the bottom. I was wondering could anybody help me get it up around 350-375 hp? What do I need to put in it during this rebuild?

 

Cam & Up... I would either P&P intake/heads with a cam swap or 1.6rrs.
Just make sure you take your time on your build and do it right the first time.

I had built a few motors none LT1 yet but have easily put down 375+ just with cam head and intake work. believe it or not I had a 305 push 300hp with simple bolt ons & valve train in my 84

 

375fwhp can be had with a mild cam and nothing else.