I had plans to budget build a 300HP d16, but my spouses cousin recommends i dont use a turbo as its not worth it, and instead, get a B series. Would I be able to get a B20 to around that 300HP mark with no forced induction?

 

No.

You might as well go K series, and that is going to take a 4piston build.

 

OP, during your research phase of this project, what evidence did you discover that supported a B20 making 300 HP naturally aspirated ???

 

If you went with the most aggressive B20V setup possible (IE race fuel, stroker kit, monster cams/compression with a CNC head) then maybe.

Definitely never on a street engine.

 

OP never said anything about setting a VTEC head on top. If he stays non-VTEC... Not even then... the most powerful one I have ever seen on pump gas made just under 180 wheel HP... that's a LONG way from 300.

Now, if the OP does go VTEC, then a full no-holds-barred, no expense spared build might get you near 300 wheel HP. That is rare air in the real world. Drag car legend/folklore. Also unlikely on premium pump gas. I have never seen anything even close to this in the wild.

Now if the OP built a "K" series with an open checkbook... the target wheel HP is not a dream.

 

...But it would be totally doable on a reasonably built turbo D series, and for way less money.

 

"Budget build" in the OP would make me immediately discourage that as well.

 

Yep... bottom shelf priced parts do not create top shelf performance.

 

As someone who owns an NA 300+hp frank swapped fa5, you really need to wake up and wanna drive it. Dailying my civic is absolutely out of the question lol. I've never seen any NA B's on the street but have seen a few at the track.
would it have been cheaper to just go boost, probably but that's not what I wanted.

 

Oooohhhh... tell us about your 300 HP engine.

 

If I'm reading between the lines he means a K24 Frank, which is totally doable.

What he said is 100% true though. You have to get up and really want to deal some crap if you're going to daily a build like that. Things are compromised, it's tough to cold start, or idles like crap, gets shitty mileage, wears out fast, is too loud, has poor drivability in traffic, name it. Some people can live with more issues, some don't have to worry about girlfriends/wives to cart around comfortably, some just don't care and are happy to rebuild their daily every 10k miles.

I think there are reasonable limits you can expect to get out of a given engine and expect it to still be reasonably 'daily-able'. For an NA B, 220whp is the most I would expect to hit, for an NA K I think that goes up to about 250-260. Anything above that and you're suffering at some point.

OP never said anything about daily-ing or even street driving his project, but the gross generality of their question indicated they had no idea what they were really asking for so it's probably not a race car. Therefore it's safe to assume they mean street car/daily.

 

Stupid high compression and nitro meth maybe.

As everyone else said, a real challenge to drive on the street. Will be rediculously loud. And throttle inputs will be super sensitive.