look no hands
Hey hook's you made a good choice going for the 451.It can definitly be built on a budget using stock rods and a 440 forged crank with hyper pistons. You will end up with a bottom end strong enough to withstand 700 h.p if you build it right,using studs and billet main bearing caps.
The heads are the expensive part,like you said. The stock head is limited to about 600 h.p with tons of porting,which you could do. The templates for big block cast iron heads can still be had.I'd start by puting the $$ in the bottom end first. Then upgrade the heads when you can afford it. This way you wont have to pull the motor.
I lucked out and found a set of alum stage vi max wedge port heads on craigslist for $900. Considering they sell new for $1600 I'm happy! Of course the rockers will set me back $1200,as I want good ones. But I am patient,and maybe I can luck out again?
Headers for a big block A body can get real expensive too,but again the hedman B body headers will work for less than $200.
Again,I lucked out and found a brand new set of hookers for $75 on craigslist.
I also got a screamin deal on some KB hyper pistons from board member Strokerscamp! Less than 1/2 the cost of new,and they were brand new!
So be patient and shop carefully. There is no reason you cant put together a 451 for less than 5 grand if you do this. You will still need to buy lots of things new,but chances are you can shave thousands from your build bill.
Being impatient and wanting it right now will cost you!