what is the weight of the 3.8l engine and 4l60e transmission? and could someone try and find the weight of an all aluminum 427 bbc?

 

A fully dressed 3.8L with automatic transmission weighs 445.33 pounds, with oil.

An aluminum Big Block Chevy weighs approximately 150 pounds empty. Not sure on the full weight, depending on whether you are running a lightweight bottom end, aluminum cylinder heads, aluminum intake, etc.

But comparitively, the 3.8L's empty iron block weighs in at 120 pounds. So You are giving up 30 pounds to run the aluminum BBC, but, when you consider that the BBC aluminum intake, and heads will weigh the same or less. In the end an aluminum BBC will have the advantage.

 

a complte all aluminum BBC weights in at 501 lbs

 

How about a small block 400 + cubic inch engine. I'm not sure if they make aluminum

 

Yup they do, the empty block weighs under 95 pounds. And those race block will punch out to 455 cubic inches.

Built with aluminum parts as well, you should be able to make it as light as an LS1, or lighter depending on how you set it up, especially with a Turbo 350 backing it up.