i have a 1980 z28. currently i have a 350 with a built th400 behind it.

My step dad has a 1968 bbc 396 and a 1960 something or early 70 bbc 427 in the garage but they both need to be rebuilt.
Its not something im going to do anytime soon but i would like to rebuild one of them and put it in my car.

which one do you think would be the best?
or should i just get an already rebuilt 454?

 

nothing wrong with either one. i would use the 427. more power.

 

thats what i was thinking about. but would it be worth rebuilding the 427? or would it be better to just get an already built 454?

 

Well it depends on what's what,you may want to use parts from both depending on what's there.
396/427 is the same engine except the 427 has a bigger bore.
Some were 2 bolt main some 4 bolt,some had cast cranks some had forged steel,some had hi performance heads and some even had aluminum hi performance heads so we need to know what is what.
If one is a 4 bolt block I 'd use that block.
If there is a steel crank in one I'd use it,same crank fits both 396 and 427.
The heads interchange too so if you have the rectangular port open chamber heads on one use them on whatever block you choose.
If both motors are the same save cid then use the bigger 427.

 

thanks that was really helpful. ill have to take a look at them when i get a chance

 

I agree 100% with Y2K! I'd always go with the 427 if everything else is equal.