Need some info on whp

Won't make 400 WHEEL with the TFS kit, I think they claim 400 crank. But I've seen well over 400whp put down with a 306 so a stroked isn't absolutely necessary. Just have to piece together the right combo.

A blower would help but you can make 400wheel with the right H/C/I and some supporting parts

the TFS kit is rated at 350 - 360 HP at the crank......with some porting and a custom cam u can get into the 330WHP and depending what other mods u have

Depends what you're trying to build it for but IMO your best bet is going to be an H/C/I (the TFS kit would work or piece together your own) and a centri blower.

You can get 300 streetable WHP from a 302/306 relatively easy. To get 400 WHP from a 302 dictates high RPM, with big cam, and related parts, which equals great drag car, and not so good of a street car. Getting 350-400 WHP would be relatively easy with a stroker or a blower, and could also be streetable at the same time.

Don't try to build a 400rwhp n/a 302 for the street. While certainly doable this is not going to be a friendly street car.

If you really want to go that route, I would recommend 12+:1 compression (race gas only), AFR205s or TW205s with a big flowing intake (Systemax II, RPM II, Victor, TFS-R with port matching). Carb would probably be the best way to go, but I'm not a carb guy and couldn't really advise you on specifics there. Add to the list a monster custom cam that put peak power in the 6500 RPM range, it could be done with a hi-rev hydraulic roller like those made by Anderson Motorsports (google Marc Arnold's Cobra and look at his hi-comp 306). Now keep in mind that spinning the motor over 7k rpm is going to be problematic on a stock block and the main-caps will walk above around 7200 rpm with a girdle and everything. Going with an aftermarket block would be preferable, but I don't think you're looking to spend that kind of money considering you want to keep the stock displacement.

Anyway, if you really want a streetable 400rwhp out of a 302W, the most affordable way to do it is with a moderate h/c/i package and some type of forced induction (nitrous, blower, or turbo). If you want to keep it streetable and n/a, then stroke it out to a 347, and put a nice h/c/i package on it. Either way is a cookie cutter solution for you.

Yeah, they took the words out of my mouth.
A 400 rwhp engine out of only 302 cubes would be a screamin' machine.
Screamin' as in won't make power until 4k rpm, and peaking somewhere around 7500+ rpm.

Don't get me wrong, our little engine LOVE to scream, but unless you set it up exactly right, and don't drive the car much on a day to day basis, it will be a chore to drive.