318 Cam Maybe Not

I wound up going with the Whiplash cam. It retains the low end torque and the idle I was looking for.
It no slouch on the top end either.

Exactly why I like recommending the DEH grinds from Comp. They are ground in a similar fashion and are not very expensive.

To the OP, don't fret yourself with details. Will this work with manifolds? Is this one right? Is this one wrong? A camshaft doesn't know if it's breathing through headers or manifolds. Will one work better with manifolds or headers? Probably, but are you looking for every ounce of HP? I doubt it. You will drive yourself crazy with details. For your application, all you need is a cam with no more than about 226 @ .050 duration (that's actually gettin a little big) and ground on either a 108 or 110 LSA. I would keep lift conservative, so you can continue to use stock rockers. So that means IMO .470 and less. Then you can also take advantage of inexpensive valve springs like Comp's 901 spring. You can do this all on an extreme budget if you stay away from snappy names like Thumpr and Whiplash.........not that those cams don't work, they do, but there are cams that can do just as well for less, so why not save the money?

One last note, there's no need to drive yourself insane on a decision. Just stick with the guidelines I posted and you will win. There's no need to try to micromanage this. You're not lookin for every last HP you can find. All you want is something snappy and reliable. You've been given that info already. Use it.

No need to make this difficult, because it is very simple.