MiketheCalamity

If I were to take the naturally aspirated route. What are things I would get? I already have a whole new exhaust (LT headers, xpipe, catback), pulleys, and of course a cai. But what are modifications to finish my engine as the most powerful n/a engine it could be? (And by finish I mean achieving maximum horsepower.) I'm assuming like ported heads and new cams, but what else. Also, how much horsepower do you think one could achieve with all the bells and whistles of natural aspiration, like the max? (You could give a range.)

stang5151

Well - you are on the way, and in the right frame of mind. I'm looking for the same thing as you. Mine hits the dyno on Monday - the tuner stated he thinks we'll end up around 400 RWHP. Certainly you could go more extreme that I did with heads and cams - mine are stage 2's from BBR.

I still have a couple more mods to go to before I have to forge the bottom end. I'll probably do a drive shaft and EWP this winter....then that is it, other than what is listed in my sig.

Yes - its alot of $$ and you could just jump right to 500 HP with forced induction.....but its fun getting to over 400 without doing so, and I've gotten some GREAT deals on parts along the way.

2007VistaBlueGT

How much are you willing to spend? You could go with a 331 stroker kit. If you want to stay 4.6L the best thing to do right now is to wait until FRPP comes out with the 3v manifold, once they do that then you can contact a cam company like Comp and tell them to grind a cam for your car and that manifold for natural aspiration. In the mean time you can get CNC ported heads like the FRPP ones, the twin 62mm TB from FRPP or the GT-500 TB kit from Metco or Moto blue will work also.

SirKnightTG

For cams, I'd go with Comp Cams SPR stage 3 (stage 2 would be ok too) with livernois ported heads. Livernois also has a 331 "big bore" stroker. This motor is sleeved. The Ford Boss 5.0 block can get more bore without sleeves. But it's cast iron I believe which will weigh a little more (not all that much I think). Also no less than 11:1 compression, maybe 12:1.

Top it off with FRPP's intake manifold being released later this year.

That should get you in the low 400's to the wheels. I'd guess maybe 420 to 440?

shanec

StokerEagle here is running a bored & stroked motor that comes out to 301 cubic inches. He's also got some kind of cams & heads and runs about 425rwhp I think, all N/A.

Vankor

And how much HP can the stock transmission handle before it starts having problems? I'm trying to go NA as well and trying to keep my car living a long time as well.

SirKnightTG

Which transmission? It seems from what I've read over the years, the manual is a bit stronger than the 5r55s auto.

But, I don't see anyone even coming close to the power limits of either trans with this engine going N/A no matter what you do to it. The issues only come when you FI or N2O the crap out of it.

Vankor

It's an 05 auto... and my brain is blanking out on the exact model transmission. How many did they offer?

SirKnightTG

2005+ uses the 5R55S. Before that ('96 - '04) it was a 4r70w which is a lot stronger of a trans. It's a 4-speed though.

Vapour Trails

No, it's not that high. I think 380whp.

It's ultra expensive to go the N/A route and you'll never have the low and mid-range torque of an FI setup (or the cool sound), just my 2 cents.