TBI cam duration

[Hotrodderzzz at aol.com]

454 tbi's are hard to find around here, v-6 tbi's are real cheap (free):

I'm building 400 sbc with aftermarket heads or vortech, haven't decided yet, 
stock crank, 5.7 stock rods, mild cam to replace 350 in 93 cop car which 
already has tbi

The Howell dual tbi stuff looked good as a complete package but the price is 
out of my budget; tpi's are available but I understand they will not support 
much hp without alot of extras such as big runners, ported manifold, big 
throttle body, big injectors, etc.  This is out of my budget.

I thought if I could add another cop tbi it would feed up to 450 hp using 
adapters on an old dual quad manifold.  I haven't looked at the ecm for a 
part number yet.

Assuming I can find a 454 tbi, how much hp will it feed without going to 
bigger injectors or making custom modifications to it?  I'm a "bolt on guy" 
not a machinist and am just learning ecm.  (I ordered the new board, but it 
appears it will be a while before I have it up and running).

I would appreciate any ideas  on a simple and inexpensive way to keep efi and 
still get 400 hp.

Thanks.