Upcoming FE build: plan coming together

[Excaliber]

I don't understand why a 428 block is all that more desirable over a 390? Both still fall short of a 427. OK, I'd rather have a 428 than a 390 (for the cubic inch more than anything else), but not if it's going to cost substantially more than a 390. If it's going to cost a bunch more, then I'd have to consider trading the Webers for the extra cash to go to the next level, 427.

[Gunner]

Originally Posted by Excaliber

I don't understand why a 428 block is all that more desirable over a 390?

I can't necessarily answer the basic question, but the resale prices show a considerable gulf between 428 and 390 cars. I'd go so far as to say that 390s are the lowest price tier, even below small blocks in the 427 car, and a greater margin below 428s than 428s are below 427s.

390s are great engines and if resale value is of no concern and the modest performance hit from smaller net displacement is acceptable, then go right ahead with a 390-block motor. If the budget is so expansive as to consider other high-end parts like Webers, diverting a few hundred more to a block that's more correct, has a bit more performance potential and will enhance resale is probably a good idea. IMHO.

As for 427 vs 428, the longer-stroke motor historically has better longevity - CS hisself used to say that 427s would blow for no reason and the 428 was a better street motor. The availability of monster-strength cranks and rods has changed that a lot but it's worth keeping in mind that 428s are second *only* to the very costly 427SO in nearly all respects. And, fa criminy's sake, both engines are oversquare with only a 0.20 inch difference in stroke... and by the time they're stroked out as most of these engines are, the difference becomes minimal.