Im wanting to swap in a 400 cube or bigger engine into my 86 trans am, its a 5 speed LG4 4 bbl. What would be the best as far as ease of swap? I'd like to do a 400....not sure how hard or easy it is. Thanks..

 

the 400 is not much different than any other sbc. Go for it. You wont be sorry, with the right upgrades.

 

What year range for the 400 sbc will work best for my trans am?

 

330817.....400...72-80...2 Bolt
3951509....400...70-71...4 Bolt
3951509....400...74-80...2 Bolt
3951511....400...70-73...4 Bolt

Here are some casting #'s The 2 bolt blocks are tougher than the 4 bolt....if you want 4 bolt main you can use splayed caps on the 2 bolt blocks...I would also look at upgrading the heads and cam as the stock ones are good for not much!