I am not sure, but I *think* the RHS heads are cast in either Australia or New Zeeland, (and enginequests are done in whatever of those 2 countries RHS's arent) it's pro-comps that are chinese
my
if building a 318 block, I'd ONLY start with '85 up core, as they have factory roller cams (2bbl cars) or at least provisions to use factory roller lifters.
400-450HP in a stock stroke naturally aspirated 318 is possible, but unrealistic for your overall desires, as it will be a very wild, high winding motor, not something that will be pleasing for a hot street driver. 300-350HP is much more realistic.
my ultra budget 318 is: a stock '86 318 short block, reringed, stock magnum heads redrilled to LA bolt pattern hughes #1110 valve springs, stock (used) magnum roller lifters, reground stock roller cam by bullet cams using their HR259/316 lobe for intake and exhaust, summit 1 5/8" headers, eddie air gap, eddie 1406 600cfm carb. 9:1 calculated compression. realistically I'd place it in the 300-325hp range. in my 3950 (without me) lb 5th avenue running an A500 and 3.55's, it will keep up with an AWD chrysler 300C hemi from a 20mph roll. it's quite entertaining. bump the heads up a little with the better flowing RHS or enginequests, and the roller cam up into the
224@.050 range and .550" lift or so, you'll see probably an honest 375hp, but the torque will be much higher in the RPM range and you'd need a pretty high stall converter and/or more gears.
realistically, stock rods with new bolts will be more than adequate for this power level.
the nice thing about the roller cam is this: my cam has 30 degrees less overlap than a comp XE262, 10 degrees less duration at .050 lobe lift, but only 3 degrees less at .2" lobe lift, and .008" more lobe lift (and .044" more gross calculated lift using the magnum rockers) than the same comp.
IF you realistically want more HP and torque, I'd start with either a magnum 360 (again, due to the roller cam) or start looking at a SCAT 4" cast crank in either the 318 or the 360. that give you more displacement, and more torque. peak power will also be lower in the rev range.
and personally, especially if you don't have an intake yet, I'd use the magnum version of the RHS's over the LA version, or either version of the enginequest heads to use the magnum pedestal mount rockers. once you start looking at aftermarket rockers, good quality magnum pedestal/stud mount are much, much cheaper than good quality LA style shaft mounts. if using stock rockers, the magnums are rated at 1.6, I've read they actually measure out sometimes closer to 1.65, while the LA's are rated at 1.5, but actually measure out more like 1.4-1.45....this means more valve lift for a given lobe lift, and more lift typically means more power.
