OK, The family and I just returned from Carova beach at the northernmost end of the Outer Banks. I drove my 2003 5.4 auto Excursion with 410 gears and my son in law drove his 2003 F250 4dr long bed 7.3 PSD. Needless to say he destroyed me on the road, fuel mileage and on the sand. I just do not have enough power. I know I will never match his diesel but I would like to get more. The EX runs good otherwise and I don't want to get rid of it. I already have a SPD Y pipe 3" magnaflow exhaust and a K&N intake system. I would like to put a 5" Rough country lift kit and a set of 315s
on it for the next beach trip and I know that combo will eat more power. I just dont know what I can do go get more guts fron the 5.4. I thought of an add on overdrive unit or a supercharger ($$). Any ideas?

 

Slap in a Lightning engine...

 

Thought of that. Got all winter to decide.

 

Yeah, not cheap to add power to these engines

 

I bought it from a salvage yard and only paid 4200 for it (owned by Penn State and had a clean title Needed a rear bumper and a grille. Also paid 1750 for a rebuilt trans. Rest is minor. Been driving it for 5 years. Still worth more than what I got in it. No payments!

 

Want more power and MPG?

One way to get both: SCT tuner from Mike @ 5 Star Tuning!

 

get 4.88 gears. runs about $700 per axle. best bang for your $$$$ until you get a Supercharger.

it'll offset the bigger tires, and you'll feel like you just bolted on +30 RWHP

you will run at higher rpm on highway however...so MPG might go down some. the higher RPM will be offset by the larger tires. but don't be surprised to see +200-300 higher rpm at speeds than you currently do




and of course, get her custom tuned. throttle response and trans shifting make a huge improvement

 

I wouldn't pay $1,500 to go from 4.10:1 to 4.88:1. I would go even further if it was mine and I wanted more power AND was going to be putting bigger tires on anyways. 5.13:1 maybe?

 

at some point though, you get negative return

typically with 35" tires, a 4.56 gearing is sufficient

seeing as he has the 5.4 motor + a 8,000 lbs rig, I suggest the 4.88 gears to offset the tires + see a performance increase.



a deeper gearset like 5.13 is just going to make highway RPM's excessive. he is already running 4.10 gears to move the beast around.



btw, what are your RPM @ 60 mph?

 

That's why I said 5.13s. He already has 4.10 gears and is complaining about the power AND he's about to increase tire size. I personally just wouldnt go ONLY to 4.88 in his situation.

 

Save the 5.4 Ex for a run-around-town SUV and get yourself a cheap V10 or 6.0PSD Ex if you need more power. It's going to be tough to get much more performance out of your 5.4 but for that money I would have bought it too!

 

Hey Beast do you live in state College? Thats where I live.

 

I have 4.30s and I'm just over 2,000 RPMs at 60 MPH. There is a fuel economy penalty I pay for these gears though, this thing simply will not exceed 14 MPGs on the highway. I work with a guy who has a V10 Excursion with 3.73s and he can see over 15.

 

What?! Seriously? OVER 15? How far over?

Is that downhill with a 30 mph tailwind? R u sure its a v10?

Holy cow.

 

Yeah, this is at 65 MPH on a steady cruise. Around town or driving much faster than that it's no better. I can't even get much over 14 at 60 MPH on the lie-o-meter.