I was hoping to get myself a F250 with the V10 but they seem to be quite scarce around here. I will be pulling a 24' 5th wheel. I have a couple of questions. What are some good engine mods that will give some extra hp and what type of a gear ratio should I be looking for. I can get a F250 with the 5.4 for a few grand less than a V10. Can I do some mods and give myself a good strong power plant?

 

look for 3.73 or 4.10 gears. the 5.4 is very capable . we mostly have 5.4 trucks at work. plenty pull 10k day in day out. i have driven plenty of them. the 5.4 holds its own. sure you can't blast up a 20% grade holding 80 mph but 55-60 is about average. the v-10 is a 5.4 with 2 more cylinders in the middle.

 

To flat out get the HP and torque out of the 5.4 to match a 6.8 you'll need a power adder (read super charger). All the bolt ons they offer (intake kits, tb's, headers...even programmers) only add 1/2 to 3/4 of what you need to get the same power and torque. You are looking at a difference of 50 hp and 175 lb-ft of torque between those two engines.

Bolt on mods don't add up 1 for 1. The package may say 15 hp for this and 10 hp for that, but you won't see 25 hp when both are added... you'll be lucky if improvement is higher than 20 hp after adding a few bolt ons. The power curves move higher in the rpm band with many of these bolt ons, thus killing your towing performance.

The 5.4 is a capable engine and will handle up to the GCWR for your truck otherwise Ford wouldn't have said so. The way I read your post it seems you're looking at how to make the 5.4 act like a 6.8... money is what you need.

I'm gonna sell the 5.4 down the river with this comment: if you want the power without spending the $3500+ for a supercharger, the V-10 is the way to go.

-Kerry

 

No my idea isn't really to make the 5.4 into a 6.8, more or less just wanting to squeeze a few more horses out of it. I was really wanting the V10 but am having difficulties finding one. As for the bolt on mods (which was kind of my plan , just was looking for some input from someone who has done some). If I could squeeze another 20 or so with some simple mods, realizing they do not usually give the claimed gains and in most cases even less when 2 or 3 are done. I would most likely be happy. Thanks for the input guys.

 

From what I have learned so far, get a cat back exhaust, K&N FIPK Air Intake with Filter, and the Diablo Predator programmer. Dont put on taller tires, this just effectively lowers(numerically) your rear gear ratio. Also, keep on eye on your COP-Coil on Plug(might even want to keep one in your glovebox), and watch for exhaust leaks, cracked manifolds. Also, never tow in Overdrive. I really didnt expect to like my 5.4, but so far its great, and all the reports on here about it, its a very good engine, not perfect, but very good.

 

I see, Zip...

I have some recommendations then. Open up the intake and exhaust as wide as you can. Piece it together over time if you'd like... the big item is the programmer, it will be a big help.

1 - Predator programmer
2 - FIPK (you choose... I don't have a brand pref, others might)
3 - TB (if available... the F150 75mm TBs may work; the 80mm Holley may fit, as well)
4 - MAF (I'm leaning towards a Lightning 90mm housing with the stock MAF, unless you swap injectors)
5 - Cat-back exhaust (Your choice)
6 - Headers (if available... see my comment about Mustangs)

at this point you'll get a bit more exotic...
new cams and new heads (Comp, Crane, Crower for cams... heads are pretty much exotics, all priced pretty high compared to the push rod stuff)
true duals (drop the 'Y' pipe and do an 'X' or 'H' for better flow)
injectors (MAF/ECU may need a recal/reprogram, usually only do this if you have heads and/or a supercharger)

things to remember -
most everything that fits a 4.6 sohc will fit the 5.4 sohc... problem being most 4.6 stuff was designed for the Mustang/F150, not the SuperDuty. Custom fab may be necessary when using those parts...

Do some research, look into the 4.6/5.4 sections of some of the Mustang Forums and magazines... you'll learn a lot about these motors which may benefit you when you upgrade yours.

Sorry for coming out at you like I did. Hope this helps you.

-Kerry

 

Now you're talkin. I was thinking along the lines of #1, #2 and #5 as a start. I will check out some of the mustang sites as well. Thanks for the advice.

 

Careful with the 'wide as you can' theory, good way to lose low end torque, not exactly what I'd want pulling a 10k trailer...

Where can you get these "exotic" aftermarket 2v heads?

The only "aftermarket" head available at any price is the Ford SVO 2V head, which flows only marginally better than a stock PI head and doesn't fit with the PI intake anyway....

 

Were not dealing with a 2 stroke where back pressure is a real issue and is maintained to keep the engine running properly. Modification does move curves around, I'm not disputing that, but opening an exhaust system up isn't going to kill torque. If that were the case, then I'd expect more people to go back to their stock systems when a simple cat back kills their torque ... after all, aren't aftermarket systems designed to open and speed exhaust flow for more power? Open it up with a good set of equal length runner headers for scavenging, many of these will actually improve the low end torque by lengthening the runner. Your restriction will still be the stock cats. You'll keep those, then replace the exhaust from those back. You won't lose the initial torque as the exhaust still backs up at the cats.

That programmer can really help when you get more into the mods. By requesting a tuner to take all your mods into account, they can set you up with a tune that'll actually produce more torque for what you have than the stock tune would come close to. The new custom tune will take advantage of your upgrades.

You're kidding, right? Man are you living a sheltered life... Like I said before: MUSTANG.

VT engineering, Patriot, Fox Lake Racing... do a search for modular motor heads, and keep in mind that what ever fits a 4.6 SOHC Windsor will fit a 5.4 SOHC. Not a whole bunch of companies, but they exist.

The heads start out as factory PI heads, then the company performs their magic and charge you some bucks. I haven't found a completely new casting, just a porting and polishing of the old design... but these flow much better than the SVO heads.

I picked up a mail order catalog (Summit) and found a set of Patriot Performance complete 4.6 heads for about $1300 in the Mustang section. They require all the other non-stock stuff to make them work (intake and aftermarket valve covers)....not for your street truck.

Exotics exist... they may be just a fancy machined PI head, but when they cost me an arm & leg, from a company that's not well known, they're exotic to me.

-Kerry

 

You need to look up the term "aftermarket"....a ported stock head is a ported stock head, it does not suddenly become "aftermarket" (something manufactured by other than the OEM) just because someone ground on it for a while. If a simple ported stock head is "exotic" to you, well then you need to get out more..... I'm fully aware of all the options for porting stock PI heads, I've been modifying Mustangs for well over 10 years, and just recently ported my own set for my truck. I quess I now have "exotic" heads on my truck.....

As far as the 'big as you can' theory we aren't talking about the average daily driver here, we're talking about pulling a 10,000 lb trailer and anything that lowers low end torque output is a detriment. Something like a great big t.b. will kill some tq down low while offering maybe a few hp up top where its worthless for towing.

 

So, being a smarty, I did ... and you know you're not completely right.

From dictionary.com -

af·ter-mar·ket
n.

The market for parts and accessories used in the upkeep or enhancement of a previous purchase, as of a car or computer.

UPKEEP or ENHANCEMENT... is adding someone elses modified OEM product not enhancing your vehicle?

About my exotic comments perhaps I am starving for a large sized aftermarket, such as the Windsor's of the push rod variety have. To me, if it's not a large scale production item, it's exotic. Let's just be reasonable and agree to disagree.

Work with me here, I know the tech stuff & some machining... not the production side. You have the experience/background to know better, then give your technical input... don't simply tell me I'm wrong about "aftermarket & exotic" and "don't open it up." Tell us what makes for better low end torque using what we can get our hands on. Not everybody is gonna be willing to dremel their heads or know what to say to a machine shop to get what they want, or know what they are looking at when they do.

I did mention that bolt-ons tend to move performance higher in the rpm band...way back in my first post. It's back to the lack of add ons that's gonna kill my argument here. If we had intakes designed for towing then we could suggest to add one of those as well as the headers...maybe a cam grind for that and an ECU mod. My thought is, since we don't have that, and no supercharger right off the bat, open all of the available systems up. I'm grasping at straws here... but I'm thinking the torque down low will stay the same and have an even higher peak, while not entirely in a useable range... it won't simply disappear. Then when ported and polished heads are added the peak of the curves will return closer ot the lower band they once occupied. The intake seems to be the big problem here and I'm hoping the headers will take care of that.

Why aren't we talking daily driver? Perhaps we should ask Zip what other plans he has for this truck outside of towing? This is partly why we are here... to not only learn, but help others. So Zip, is this strictly a tow vehicle or what?

-Kerry

 

I have a 98 Lariat SC with 5.4, 3.55 gearing and the tow package. It has 118K miles on it now. I have a K&N filter element and 3" exhaust, muffler and tailpipe made up by a local exhaust shop. My truck runs and pulls great. A 3" exhaust is also offered by Gibson and supposedly offers more torque than having 2 tailpipes coming out of one muffler. I can pull my 17' trailer with a car on it at 75 in OD on the highway and I truthfully don't feel it. Going over the mountains at high elevation is another story though. Last summer I brought a 57 Ford back to Illinois from S. California. I just test drove an 06 F-150 and F-250, both with 5.4's and still love my 98. The F-150 seemed much more responsive than the F-250 and drove very nice, which you would expect with the same motor and less weight. I'm tempted by the rebates, but actually I'm not crazy about the new F-150 styling yet, but I do like them.

 

Yikes...

IMHO re-gear to 4.10 and you'll be set. Torque multiplication is a very nice thing, you'll get way more pulling power from a re-gear than any bolt-on. Unless you bolt-on a blower.

I've got a blower, but I've had the blower belt break while I was towing. Remove the belt = "regular" 5.4 for me. With the 4.10s, it still tows our 7000-lb boat/trailer very well. And I've got a non-PI motor, rated at just 235hp.

BTW - she tows quite nicely indeed with the blower. It gives me a very flat torque curve, around 400 lb-ft or more rear-wheel torque from 2500rpm on up.

 

You could always order a Super Duty with the V10 and not worry about a thing. The difference in invoice cost is $480, well worth it if you need the V10.

 

Well I got one. 99 with the 5.4 and 4.10s. Seems pretty solid and after a couple of issues fixed by the dealer I am happy so far.