AgentFrosty

OK guys, like the title suggests, this is a 400whp n/a build, pure and simple. I'll be going about this in the next year or so, hoping to have it completed by the time early spring rolls around in 2015, more specifically late March/early April, so I'll have plenty of time to get this build together.

Now I've seen several threads about 400hp n/a crank. That's not enough. I want at least 400hp at the wheels, n/a. There will be a bored and stroked shortblock coming, though I haven't really decided yet on which company's shortblock will get my money, though i'm pretty confident any of the choices will have what I need. I'll also be going with Stage 4 Livernois cams, as I'd like this puppy to rev to at least 7k, along with the Ford Racing intake manifold to make sure she breathes well enough on that end.

My specific question to you guys, which i'd like your opinion/technical expertise on, is which set of ported heads to choose. My three choices that I've narrowed it down to are Ford Racing's High-Flow CNC'd heads, Livernois' Stage 3 heads, and LastCallRacing's PowerHeads ported heads. The Livernois and Ford Racing heads are close in flow, 291/191cfm versus 295/200cfm intake/exhaust for the Ford Racing and Livernois heads, respectively. The PowerHeads flow less on the intake side at 271, but flow 225cfm's on the exhaust side. My question is, should I go for all-out flow with either the Ford Racing/Livernois heads, or will 271cfm's get me there with the extra exhaust flow of the PowerHeads?? Like I said, i'll have as much intake flow as possible with the intake manifold and cams, plus I've already got the prerequisite longtubes, catless x-pipe and catback, and CAI/Throttle Body mods installed, with an electric water pump and UDP's on the way.

Now, to make this post just a lil bit longer here, I wanna say this: I don't wanna hear about what I "should" do instead of this to reach 400hp. I don't want boost. I love a high-revving n/a V8. The sound, the response, the linear power delivery...I don't drag race, I road race and do lots of twisties. This is the kind of engine I want, for the kind of car I have and the way I use it. This will cost a lot of money but that's how the game goes, so I don't want to hear about cost-effectiveness either. I have a specific set of goals to achieve, and I will spend the money to get them. So put all that stuff aside, and give me some help/advice. 400whp+. 7,000rpm+. I want it. Help me get it.

outceltj

I haven't heard of it being done yet on the forums or at least this one. Good luck keep us updated on your progress

hootie_john

Not to rain on your parade, but....

If you want 400 at the wheels NA, you better get the biggest block you can....you'll need it. I've not read of anyone hitting it on the 4 forums I frequent regularly. The Brenspeed 326 would be a good place to start I'd think.

breathegood

I don't think you necessarily need a whole lot more cubes than the stock 4.6l for 400whp, but I would definitely be thinking about 11-12:1 compression ratio and 8000rpm redline. There are a few that have pushed to between 350-370whp on the stock bottom end with full bolt-ons + heads and a pretty radical cam profile. I think it can be done, but I am skeptical about how drivable it will be on the street.

Nuke

400 RWHP on the 4.6L costs a good deal more than SC'ing it, plus you'll have a barely streetable and likely somewhat unreliable vehicle. I've heard of guys reaching around 375-380 without totally breaking the bank but let us know how you make out.

smokievol

5.0
5.4
SC
4.6 plus loads of cash, and more cash and then some more, use the search to find different posts on who have done this with the 4.6

outceltj

If u seen the post for NA 400 hp at the wheel then u know what to do.

danzcool

Stroked and bored with good heads and big cams & high revs should pretty much get you there.
If you wanted to be a little different, you could start with a 3v 5.4 out of an explorer and bore it to 5.8, should give you a bit more of a step up.

At 400 or more RWHP, you may need to step up to 42LB injectors and either the gt500 fuel pumps or KB boost-a-pump to make sure you have enough fuel.

definitely looking forward to where you end up and how you get there.

SpartaPerformance

For 400 RWHP I don't think you'll need much or lose much if any streetability, the new FRPP M-6009-A46X block with ported heads, hot rods and intake make 440 BHP, I'm sure a compression bump to 11:1 and a N/A specific camshaft will be more then plenty for your goals.

smokievol

I've seen several post, and some people blow a ton of cash,,,some then get a SC.

Like you have a SC.

The ease of of adding a SC and then having the surge of power is hard to overcome.

You of course can build up your bottom end and then hopefully be happy......or add a SC later. That's even more cash.

Might as well put in a 5.0....and then add a SC.