It may be cheaper to take that 350 and put a low profile Blower on it.
9:1 static compression recommended
Blower cam 114 lobe speration
run ya 6 to 8 lbs of boost thru it and Cometic head gaskets will be fine.
The Hp is gonna go close to 500 and the TQ will be a nice flat Curve possibly passing the 600 ft lb mark.....a natually aspirated 427ci will not produce a flat Tq curve like this 350ci blower set up will.
if you price the Blower job out wisely.you could get out for under 2,000-2500 (tops)
$1100-$1200 for used b&m 144 blower ( u can find them for this price)
$400-$500 for blower cam and roller hydraulic lifters
$200 set of cometic head gaskets.
$150 head studs
Could be another $300 to $400 to have your chambers opened on your heads to lower compression if your higher than 9:1 compression..if not this is money you do not need to spend.
then if you wanted up the anti on up..you can place a E-85 carb on top and make another 10-15% hp and Tq.
just sharing what i would do instead of dumping the heavy cash in a new 427ci...to do a 427ci SBC The right way is gonna cost you 7k to 10k
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Bjuice..
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