383 ci smallblock
-350 flat-tops on 400 rods
-fully ported 882 casting heads (est:11:1 compression)
-aftermarket intake portmatched and gasketmatched (Edelbrock?)
-800CFM Qjet, tuned for motor, L69 cold airsetup, K&N
-headers, full 3" exhaust, no cats
-little stuff like electric fan, no emissions, etc.

Is this a combo I can expect an honest 375Hp from on the flywheel?

 

Your CR will be about 10.2:1 with those smogger heads.

You might get that much HP, maybe, if you use a Perf RPM intake, and a decent cam, and you end up with a real good port job on those heads. Although, those heads have been well known over the last 25 years for creating disappointment. I personally throw them in the garbage (literally) when I find myself unable to avoid owning any of them. I won't build a motor out of them, ever, not for any purpose whatsoever. A set of undercut-stem valves will help somewhat. Definitely get the spring pockets cut for 1.45" springs, and replace the pull-out studs with real ones. I'd recommend a Comp XE274H cam. I had that in my 400 with 1.6 rockers and better heads, it ran great.

Use a 1" or taller spacer between the carb and breather. Again, that's what I did on my 400.

 

...good advice on the heads. I had a set of 291 heads and they were cracked and unuasable. any advice on what I should be using for a set of heads without breaking the bank?

I can get a set of L31's for $500, ready to go, but then there's more money for an appropriate intake...I hadn' t planned on spending more than rebuild money on heads, so we're on a budget here...