My mods: MPG/Performance

[Dixie Design]

Here's the lengthy post I promised describing my individual experiences with my modifications on my truck (to date 3/13/09)

I'll start off first by stating the obvious, I know not everyone will have the same results, some may be better some may be worse. It all depends on driving habits, geography, weather etc.

When I bought my truck new in 05 my daily commute was approx 90 miles roundtrip to and from work (Savannah to Hilton Head). I averaged very close to 20mpg on that commute and as low as 14-15 in the city. I made no modifications to my truck until I moved to South Georgia.

I moved to South Georgia and started the modifications around 30,000 miles. First I installed a leveling kit and put on larger tires, 265/75/R17's. My fuel economy suffered, dropping to 17 hwy, but I lived in a rural area and didn't do much "city" driving, not a lot of stop and go.

I added my S&B Cold Air Intake kit around 32,000 miles and my fuel economy shot back up to 19mpg hwy. I was pretty impressed. I felt like I had a little more "getup" in the higher RPMs, over 2800-3500 especially, can't honestly say I really "felt" much difference at lower RPMs.

I moved to Valdosta, GA, a small city, and the miles had racked up. At 85,000 miles I was getting about 16 hwy and 13 city. I swapped out my stock muffler for a SI/SO magnaflow muffler. No noticeable performance or mpg gains, just sounded a little better.

At 87,000 miles I added the Edge Evolution programmer. Fell in love. It REALLY woke my truck up, better throttle response. My truck felt a LOT more powerful at any RPM and once my “need for speed” subsided, my fuel economy went back up to about 18 hwy and 14 city.

At 95,000 miles I changed my exhaust setup to true dual Magnaflow exhaust, x-piped with high flow cats. I can't really promise much for performance gains, I'm not sure if I felt more horsey or just sounded like it, . My fuel economy went up again to about 19 hwy, not much of an increase at city.

Shortly there after around 98,000 I cut out my rear cats (the high flows) The only difference at that point was the sound a little louder, no performance or mpg differences.

Right at 100,000 miles I upgraded to a Gryphon with a custom 87 octane performance tune, right after my 100,000 mile maintenance which included the plug change. LOVE the Gryphon, my throttle response increased, my CAI didn’t sound like a sheep on sterioids anymore and my fuel economy is better than ever! 20.4mpg on my last highway tank and I’m steadily getting 16-17 on my weekly driving to and from work, grocery store, church etc.

I hope this helps some folks, my underdrive pulleys are sitting in the garage to be installed tomorrow and I’m ordering an eFan kit from Troyer today (if Crystal ever calls or emails me back). I’ll update after I’ve got some miles on those mods, planning to wait a while to install the eFans so I can see how each effects my truck independently.

Any questions, comments, or requests for more info I’d be happy to oblige!

Neal

[Power Hungry]

Lengthy??? Apparently you've missed some of my posts. :ROFL:

Good write-up, Neal. It nice to see everything in stages and to get a feel for what worked and what didn't.

Keep us posted on the pulleys.

[Dixie Design]

Yeah, I was planning to be a lot more lengthy than that, then I realized we're dealing with a much more "mature" and eduated crowd over on these forums. Not to mention there's not a herd of people who "know everything" and jump at every opportunity to bash your mods and testing. Shortened things up when I didn't feel like I had to enroll at the University of Phoenix online to get a degree in engineering, meteorology, physics, chemistry etc before posting.

[Power Hungry]

Originally Posted by Dixie Design

Shortened things up when I didn't feel like I had to enroll at the University of Phoenix online to get a degree in engineering, meteorology, physics, chemistry etc before posting.

That's way too funny!

[Caforddude]

Cool write up. I wish I had installed my mods in stages to see what each did.

[Circuit]

I would like to know about the OPs experience with the under drive pulleys and e-fans. I am looking at doing the same thing eventually and just so happen to have the same 2004 xlt 4.6.

Any information about them would be helpful to me. Thanks.

[Dixie Design]

Believe it or not, I STILL haven't installed the efans. Now that I've sold Dixie Design, I think I'll have time!

[BlackSTX]

LOL Having to have a degree....

I know what you mean, I have seen that quite a bit on other forums.

As far as the mods I have done:

Started with a Magnaflow SI/DO exhaust. It definitely improved the feel of the truck; it felt much lighter on its feet, and accelerated better. Not to mention, it certainly sounded much better too!

Next I installed my CAI, AEM Brute Force. I can't really recall how that felt, but if I can recall, it did help it out.
I also installed a 180 degree stat, and added some water wetter to the coolant. I do not like running my engines hot. Perhaps it's me....I'm old school, and prefer to go with what I knew from years ago when I wrenched and assisted friends on their race cars.

The last mods I have done were with the programmer. I ordered an Edge, but quickly sent it in for the upgrade and custom tunes (about a month after getting it). It felt good right out of the box, but I thought I could hear a hint of ping, so rather than risk damage, I had the tunes done.
The tunes are great! I have lowered the shift points a little bit, but bumped up the firmness to 18. As it shifts 1-2 at about 45, it's pretty good. It hits quick, but I'm not chirping the belt where it's currently set.

Furthermore, if I do more highway diving, the mileage comes up quite a bit; despite my lead foot. Around town, to and from work, I have been averaging about 14-15. I'm only 3 miles from work, so it doesn't get to operating temps very long before I'm there.

Next on my list is going to be UD pulleys and a Gator Grip belt too. Hopefully in the spring I can manage to swing for a set of gears (4.10-4.30:1). These darn trucks are just too heavy making them very polite when it comes to leaving the lights. Besides, 17 second 1/4 miles are just way too slow....we're talking getting beat by my mothers old Chevette slow.

[fordkindaguy]

Black stx, i saw you mentioned chirping the belt, mine does this going from 1-2 good or bad? i have a 4.6 cai & flowmaster catback

[Jackpine]

People's experiences vary. My economy improved with the Gotts mod, and, it improved with an Edge and then got a bit better with custom tunes.

One thing, you'll be able to use the "canned tune" Gryphon on BOTH trucks, as long as you return one to stock before moving it to another. So, you'll be able to see what it does for both of them. Once you get custom tunes, it becomes "married" to one vehicle and you lose that choice.

I'd say it's definitely time to change plugs if they have over 100K on them. Use Motorcraft plugs.

If you don't tow, just get an 87 performance custom tune when you make the choice of truck to use it on. Until you get custom tunes, use the Level 2 tow tune as a daily driver. It's a good all-around tune.

If the tires you put on the older truck are larger than OEM, they will probably hurt your mileage. They increase the load on your engine both during acceleration and at cruise, even if the cruising rpms are lower.

- Jack