No amount of money will get more than 200 hp or 250 ft lbs of torque from a non supercharged 235 with a stock head,modified or not..Leo Sanducci,who runs a successful 292 powered drag car,and used to run a 261 powered drag car,told me his 1/4 mile time and car weight suggested about 275 HP with a heavily modified stock head on that 261.This is a limited use expensive drag race motor,spun nearly to 7000 rpm and with no power at all below 3000 rpm,totally unsuitable for street use.In addition,other than a few articles written 50 years ago,there is no reliable dyno testing figures on the 235-261 engines.
There's a lot of BS about the power from these old lumps.When I was building the 302 GMC for my 37 Chevy truck,guys talked about massive power from the 302's.In reality,for street use with a somewhat stock head,they make about 250 HP at 4500 rpm,but with good torque,maybe 320-350 ft lbs at 3000 rpm.The 302 head,with it's large ports and modern wedge shaped combustion chamber with unshrouded valves,make a 235 head look like something from the stone age.Like the guy says above,in my 2900 lbs 37,250 hp makes it go pretty good.
Buck for buck,nothing can outpower a 350 Chevy,and for the street,there is no replacement for displacement.
