I don't know what your mechanical skills or budget are but if you can assemble a long block I went with this from Tri Star for my budget build Regal project.
•4 bolt main block •9.5:1 compression ratio (with 64cc cylinder heads) This 355 Chevy engine is ideal for a shortblock on a budget. Tri Star Chevy short block crate engines are CNC blueprinted and machined to ensure accurate fitting. Give your high performance crate engine new life with this...
www.tristarengines.com
And then added a set of these aluminum heads along with a hydraulic roller cam and should be at around the 325-350 HP range.
United States. Alloy +B4: H16. List of Standard Alloy Characteristics. and lighting components for aircraft. flat tappet and a hyd roller cam, then it would be too much for the hydr. flat tappet cam, and create a wear issue.
rover.ebay.com
I shopped around for the best prices for name brand rockers, pushrods etc blasted a used RPM air gap intake and have a refurbished Holley 670 and this thing runs great.
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