Big horsepower 318 builds

PRH said
My take on it is....... unless it was built to fit within some specific set of rules....... or someone took it on as a personal quest....... I look at it as.....why would I do that?
(When a 500hp 408/416 will be easier and likely cheaper).

It’s going to require a fairly high level of effort to end up with a 500hp 318.
From a hp/ci standpoint, it’s like building a 446 at real close to 700hp.

I have built a few 440’s that got into the 700hp range(a bit over 1.5hp/ci).
Those were fairly well thought out builds with good cylinder heads and fairly stout cams.

I’d be happy to follow along though, if someone decided to “go for it” with the 318.

There's a big difference of 1.5 hp/cid depending on what engines your talking about. small engines you can get there with factory ish parts.
170 /6 would be 255 hp
273 would 409 hp

either of those wouldn't need nothing too exotic

660+ hp 440 is a serious build, a 500 hp 318 wouldn't think you would need anything to crazy over a 340/360 408/418 all would need similar heads cam level etc..
But ya at that level 500+hp it makes little sense to build a 318 and even 340/360 at that, other than you want to.

There less than 20 cid between a 360 and 318 with the same crank and overbore and about 25 cid with a 340, but ya there better piston selection and the slightly bigger bore for similar or less money makes the 360 the better choice. But in the 425 hp and under I don't think it overly matters which one of the sbm 318/340/360 you build especially if your willing to gear and stall it properly. But since most only want to run 3.23 or 3.55 gears 360 is gonna be the better choice.