Hey All.

So I'm sitting here waiting on my tax check to show up right. I've got this nice list together of parts I'm going to order from Summit and Lethal Performance to assemble a 5.4 shortblock, and while I wait for the check to show up I have lots of time to think about how I want things to pan out.

The shortblock assembly and parts are for the most part decided, as well is the fact that the motor will recieve boost once installed and broken in.

The method of boost is undetermined, but will be either Twin Turbo or Vortech T Trim.

What I'm wondering is, is the 5.4 worth the time and hassle ? No matter which boost method I choose the 5.4 will complicate things. If I use the Vortech then brackets fitting, bracket strength, and other misc issues come into play, whereas if I go turbo custom headers and trying to snake piping around areas that are tight on a 4.6 could prove to complicate things as well, even with a tubular K member. I relize the goal of the boost game is to make maximum power on minimum boost and that the extra cubes should help with that but is the 5.4 worth it?

Anyone that has gone through the swap, was it worth the swap and was the extra torque noticable ?

I guess my thought is that if I'm going to boost it anyhow, why not let a few more PSI do the work instead of the motor. I'm not looking to build the fastest baddest car on the road, there is no way my budget could account for that. However I'd definatly like to not have to worry about the whipple and KB2.8 4v's running around (both 03/04 and 07) that seem to be putting out 7 and change.

I'm all ears, love to hear your opinions. Talk to me.

 

If I were you, I would be asking any 5.4 related questions, in the 5.4l swap section. There are over 100 pages worth of great knowledge and first hand experience in there. Talk with R3d and some of the other guys in there that are doing the swap as we speak. 5.4l has more potential being bigger displacement and the torque is crazy.

 

This board has no 5.4 swap section.

The 100 page thread (which I have read every page of) is stickied here, just a few posts above mine. Which is why I posted here because those guys read this forum.

Everyone says the torque is insane, but the torque ratings you see online are with a truck intake. I'm curious if converted to a mustang intake if that info remains true.

 

To give you an idea w/ the torque, in that thread, someone mentioned where a guy used a lightning lower and cobra upper to make his intake and he managed 340 ft*lbs torque. Now, add a real intake w/ runners and you what everyone means by sick torque. Not only that, the 4.165" stroke (which is longer than some big blocks) helps out too. As for the Vortech, the worry you'd have is if the holes line up w/ where the bolts go into the timing cover. I bet chances are they do so your only worry is connecting it to the TB. However, don't take my word for it, since this is my assumption.

 

I'm highly curious what that number would be with a real mustang intake. PI, Bullitt, etc. I'm not to far from that same torque number with a n/a stock head, stock cam, stock intake 4.6L. I'm told with a bullitt or comparable the HP would be 320ish and the torque 370ish on that setup. I did some searching for posts about that guy and found his track times as well, and that he has the intake for sale.

I'm sure the stroke should help torque, that always seems to be the case although Modulars seem to be picky bitches and dont always work the way they should.

I've heard the bracket will line up, and I've heard it wont. The 5.4 has an idler missing that the 4.6 uses for a cent blower from what I can see, which could pose a problem. I've also read on another forum that if the accessories werent reinforced they would move under boost and toss belts... not fun.

 

a stock PI intake is a serious restriction. Nonetheless, with even a mild aftermarket cam the gains get serious fast. Stage 3 cams and a short runner got a mild motor to 340/340. Ported heads, stock cams and stock shortblock got another chap 289/366, an ugly tractor turbo and a cobbled up lightning lower got some other dude like 480/5xx.

Whatever you could think about doing to a 4.6, doing it to a 5.4 will be better. It's not that tough and I'll bet a dollar the blower bracket lines right up. I'd personally go with a 70mm single turbo and shoot 12-14lbs into it if I were to have such an option.

 

R3d, I agree 100% on the stock PI. I was more or less saying a mustang style intake and not the truck style intake thats known to choke these motors up top.

If the 5.4 can make the power better, then I'm all for it. I dont want you guys to think that I'm a hater, I just like to do my homework is all. It seems that the 5.4 is good for about 20ish RWHP over the same combo on a 4.6 with about 50 RWTQ gain.

That setup you mention, on 14ish psi - what kind of performance are we talking ?

 

the intake and the cams are the secret sauce to unlocking the 5.4 in 2v form. With a better intake like the HPS Hardball'r and even a little better cam you should see pretty impressive gains.

Power from 14lbs with a proper cam setup and a good intake should be well over 450hp and probably teetering around 500+. Torque would be a major concern at that point too... I'd call mandatory 31 spline axles, welded axle tubes and in floor subframe connectors as well as torque box reinforcements.

There's nothing stopping such a car from seeing mid-11's other than traction.