I am planning on putting a 402 bbc in my 84 Z28. I have found the motor mounts, headers, etc.. I am trying to find out any additional informatin for when I put in the motor. My main concern is the ac box on the firewall. Even though I am not hookin up the ac on the car I would like to keep the ac box. If you have any tips for me I would appreciate it. Thanks

 

I have seen the topic of a BB in a 3rd gen come up here a few times but have not seen any one that has done it here yet.
One thing I could advise is if you have not built the motor but have it in peices (or another one apart) then you can mock it up in there and if you have to mod the box you can do it all bofore you are ready for the final install.
And post some pics of it!

 

i have the best tip of all keep that heavy motor out of there and leave it a small block lol

 

Put some aluminum heads and intake on that big block, and the weight difference between the big block and the old cast iron clunker that was in there will be negligible.

 

the 402 big block only weighs 100lbs more than the 305 clunker I had in it. And that heavy big block ran a 13.0 in a 70 442 blowing the tires loose, which is a lot heavier than my camaro