Big horsepower 318 builds
Also, the theory "you just have to spin 318's higher" is just a theory.
I don't get this one, don't know why you would say that?
To me there two main ways to go about building an engine, for a certain powerband and gearing or for a certain hp level and gear and stall to work with the final powerband results. To a point most are a combo of the two.
The 1st one say you pick 3.23 and idle to 5000 rpm with peak hp being about 5000 rpm, obviously since rpm is fixed torque is the only main way you can build NA power so the bigger the engine the more hp you'll have most street type engine fall into category.
2nd is to pick say 500 hp and pick a displacement and build.
So a 318 vs 360 vs 408 you would have to displace a certain amount of air, there's a rule of thumb saying about 1.4 cfm for every hp, not carbureted but actual displacement (1.4cfmx500hp=700cfm) so if you run a 390 cfm carb or a 1000 cfm carb the engine is gonna pull 700 ish cfm's through either.
At 100% VE using cid x rpm / 3456 = cfm
a 318 would need to spin 7608 rpm to displace 700 cfms
a 360 would need to spin 6720 rpm to displace 700 cfms
a 408 would need to spin 5929 rpm to displace 700 cfms
Obviously depend on how well you design your combo they can overlap eg. a poorly built 360 peaking at 7200 rpm and a well put together 318 peak at 7100 rpm but I don't think you could build the 408 terrible enough for the 318 and it to have similar powerband.
So I guess yes there's exception and there's enough variables to make it, "it's just a theory", but it's generally true smaller needs to spin higher.
