Well, my block (casting number 3970010 350 4 bolt) came with 462624 heads which I have heard are Chevy's "lightweight" heads that are 6 pounds lighter and are said to be crack prone. I want to upgrade to Vortec heads because it isnt all that much money from GM Performance. I haven't gotten the intake yet, and I wanted to get a new one anyway.
I also hope the heads/intake give me better gas mileage than my current configuration too. If anyone cares to list the mileage they get with their configurations and vehicle, that would be awesome. I just want to get 15 or better city installed in the astro. Also, would a 650 cfm carb be what I need? or more/less?
I meant to say that I have a 350 i want to put in an astro, and the G20 is what I'm driving now. I was saying i get 15 with it currently and would like to get that or better on the astro project. Sorry about the confusion.
Thanks again!!