[goodyear1984]

a 347 would handle a turbo no problem.but rember if your goin to turbo the engine you are going to need to have lower compression ratio and have the right cam and right carb.the only reason y i would say the 347 wouldnt handle a turbo is the block.the stock blocks really are not that strong pretty much like 550 ish horsepower is about as high as i would go and a main guridle is a must, so what im getting at is if u build a 347 and say it makes 450 hp then u turbo it ur gonna be cracking that block in half.now if you go with a $2000. dart block then u have a block that will hold. 2 grand is alot of money but the dart block has pretty much all the machine work done so if u think about it u will save around 500 bucks in machine work with the dart block.as far as heads go you get what you pay for.i personally would spend the extra money and get afr heads,if you seen the quality of them u would know what i mean.i have patriot freedom heads on my 347 and they do work good,they were like 800 bare then by the time i got good valve train for the heads i had over 1300 into them,dont get me wrong they work good but for the extra money i would have got the afr heads and i know i would have gotten some more hp.i could have bought the patriot heads assembled but there cheaper heads and who knows what brand valve train the company would have put in and u know afr valve train would be good.so basically as far as heads go just get the assembled afr heads.well the gas millage in my 500hp 347 is not great i get around 10mpg but i also want the most out for the motor so i have a quick fuel q series 750 .if your worried about gas millage then i would just stick to a 302 ho bottom end slap a set of arf heads on it and a paxton super charger, you would get ok gas millage untill you boost it .or a mild 347 with a basic holly street carb.me personally i could never build a 306 just for the simple fact that u spend a little more and get a 347.