5/16 line is all you need for the swap at this level of performance

you would be surprized just how much it will support before needing to go to 3/8 line,IMHO

result do vary

and I was thinking about 350 hp myself

close enuff

and jumping from a stock 150 hp to 300hp is a big jump IMO,and the 5/16 line is doable

but a 4-v swap to a stock teen is not going to be that much HP to begain with..might bump it to 160 hp

headers have more of a boost than just swaping on a 4-v to a stock 318 in my book

5hp...w/ 4bbl carb/intake only...mabey... with a tail wind.

Dual exhaust is a must.Headers a plus.

i would use a edelbrock 600

I run a 9800 series Thermoquad on mine with the 340 exhaust all the way back and the early manifolds. works great with 95 or 92 jets and I think the 340 metering rods.
If you know how to work on one they are pretty much fully tweakable to run on just about anything. Mine pulls smooth, starts cold and runs great first try, and gets good MPG and power. Plus they sound awesome at WOT

My first car was a 318 Duster.I used a 600 Holley (old 6909) a Holley street dominator intake, stock 340 cam from the Chrysler dealer,and 1 5/8th's cheapo headers with Walker street Hemi mufflers spec'd for a Hemi Road Runner I got from NAPA.That combo worked great in that Duster and with a shift kit in the 904 and 2.76's out back,it got over 20 mpg easily.

360 heads, thermoquad and a stock 68 MT 340 cam and some headers and duals. That ought to make a decent running car.