sbc 350 rebuild

i sent my block in too get acid dipped and the mechanic informed me that the block will have too get bored .030 over;... will this result in an any overall changes performance wise? if so what can i expect?  

i just checked the head numbers online. 333882 and 354434 not a matching set and from what i hear the 882 is a piece of crap  

Overboring will obviously increase displacement, so your output will increase. How much? Well, assume that the specific output will stay the same (which it should stay very close) and make an estimate. It will usually be around 5-6 horsepower at peak.

I can see why whoever did put those two heads together as they are very similiar but regardless for best performance it's probably a good idea, but neither using a open chamber smog-era head with dual heat-risers.  

Yep the heads are junk and have different size chambers.

Boring the bolck .030 over will usually boost the torq no more the 5 ftlbs.  
Horsepower sells Engines and torque wins races.

i am considering putting '96 vortec heads with the matching edelbrock intake.  good choice?  

What happened to the victor heads you were going to get.

how much power are you trying to get out of this engine.  
Horsepower sells Engines and torque wins races.

the guy that had them for sale refuses too answer my calls =(  my goal is 400 max if thats not too much  

You should be able to reach your goal with the vortec heads.  
Horsepower sells Engines and torque wins races.

Also be sure to get the valve springs to match the cam.  
Horsepower sells Engines and torque wins races.

as in what valve force (200 pounds for example) or what do you mean?  

Excuse me, those two castings numbers are not very similar - thanks to Pontiacman for making me realize that there is a large dissimilarity in the chambers...

Valve springs are a terribly complex component of an engine and just judging the forces they exert on the seat sometimes isn't enough to justify a choice. To completely eliminate any guessing games it's best to use the exact springs the camshaft manufacturer recommends for use with their cam - that's why most cam manufacturers also manufacture or distribute valve springs.  

i called elgin and they recommended camaro z28 springs whatever gm part number they may be...  

Here are to recomended part numbers to use with the elgin .480 lift cam P#VS739R and RV943X.  
Horsepower sells Engines and torque wins races.

Z28 springs are about as mild as you can get as a stock upgrade...

I'd be careful of some discount part distributors posing some really crappy springs under the title of GM "Z-28 springs," as they're very common anymore.

They are the stock diameter (about 1.25") and usually make around 110 lbs on the seat and about 300 lbs at .500" lift. Don't use anymore than .500" lift, even if some others say differently.  

Which elgin did you call elgin industries or elgin cams.  
Horsepower sells Engines and torque wins races.