So far:
- K&N cold air intake
- cat-back exhaust with a glass-pack muffler
- Granatelli 0-ohm performance spark plug wires
- E-3 plugs
- MSD ignition coil
- Electric fan on thermostatic control switch, removed OEM clutch fan & components.


A difference in acceleration and throttle response can be felt, still calculating the MPG after recently installing these things. I have some quick questions for you guys...


1. Anyone here run headers on their 4.2 truck? What is it like, as in heat dissipation, sound, power increase, MPG improvement? Did any bolt/studs break off when you removed the stock manifolds and if so how bad was it to repair?


2. Any experience with the SCT programmer, or any programmer for that matter on our 4.2 engines? Maybe some type of custom tune? How did it work out for you?


3. Any recommendations for better/improved fuel mileage/MPG?


Thanks guys!

 

I did go from 235/70r16 Hankook Dynapro HT tires to these 265/75r16 Kumho Road Venture AT51 tires. Got a good deal on them brand new, and kept getting stuck in the grass when doing gardening/random work with the truck. I am sure this affected the MPG but made a big improvement when driving on uneven/slippery terrain.

 

My 2008 4.2 manual transmission baseline dynoed at 175 hp and 221tq at the wheels on a dynojet. After an SCT flash tune (handheld programmer) and a "gotts mod" it picked up 11hp and 21tq for a total of 182hp and 242tq at the wheels. The truck has 4:10 rear gears and is otherwise stock other than a rear end girdle and an added oil cooler and airbag helpers for towing.

 

Thanks for the response. Since that post I have also added a set of shorty headers and magnaflow direct fit catalytic converters since I had a bad rattle. Turns out a converter was broken inside.

Also finally ordered the SCT X4 tuner. Figured a good tune should compliment the couple performance upgrades I have done.

 

My 4.2 came from a 06 f150, I paid $100 for it crank and 1 rod was junk. I was expecting better mileage out of it but hands down outperforms the 4.0 so I am happy with that.
Ranger
-Ported and polished heads -Comp cams smallest cam they make(my number 3 bearing was a part of the cam for tear down, had to upgrade)
-Roller rockers
-SN95 short tube headers...was the idea until it went in drivers side has a BBK short tube now as well.
-Full custom stainless 2 1/4" to race cat, to 2 1/2" out exhaust
I was going to run electric fans but I didn't have the real estate between the radiator and pump hub, explorer 5.0 fan. I am going to get ahold of my tuning guy see about having a tune done on it.

Curtis

 

I've got the electric fan, an underdrive pulley, cold air intake, custom tuning, dumped exhaust, 4.10 gears, alloy wheels, blah, blah, blah..........it's still a 4.2 & you are not going to get any significant improvements.

Do what you want because you enjoy the mods. But you're not building a muscle car.