Ok guys need help my buddy bought a 2008 F150 4x4 4.6 40,000 miles. It has straight pipes sounds good but is real real slugish on take off wont even spin the tires on gravel!!!!! He asked me what I thought he should do to pick it up, since I had a 01 gt with 4.6. So I told him maybe k&n cold air, maybe injectors and cams but he was wondering if he could just do this with a programmer or what he should do? OH and it has 373 rear gears. Any help will be great.

 

First off, see what size piping is on the straight pipe makes sure its no bigger then a 3" if its a single pipe. Best bet is to run a muffler to help with a little low end. But easy and simple mods for best gains would be a programmer or custom tune. I hear PHP is really good plus you get the cool gauges on the pod. next would be a good intake, i am not sure what the best intake is for the 4.6 but im sure he could ask the tuner. Power Hungry Performance - Gryphon™

Cams wouldn't be a waste of money but would cost a lot and may not gain much. But injectors would be a total waste. the stock injectors are plenty for the truck at this point.

 

Does he know what his gear ratio is?

 

I have a 4.6 and got an edge and it helped tremendously. For a quick easy boost, i would definately recommend a Edge

 

Just check out the fuel pump for pumping the right ratio of fuel to the engine.Mostly fuel pumps are responsible for this kind of problems.

 

ok thanks for the inpoint guys and his gears are 373's. his pipes are 21/2" from header back to 3" tip they are true duels. He is going to look at the air intake and the edge evo this weekend anything else he should look at?

 

does he have a x pipe installed? if not he should, i hope its just not two pipes going all the way back!

 

cold air intake won't do anything but look cool under the hood. no performance increase at all.

 

Not to mention a 4.6 even in 4 wheel low is far from a performance vehicle.

My 07 F150 2WD w/ 3.73's is very sluggish on takeoff too but its because of little motor and lotta wieght.

I agree the cold air kit is strictly for sound and looks. The exhaust should help though. It sounds like the correct size and should increase mileage and performance. The computer tuners like the Edge are very good but are very pricey. If you hang on to your truck for a few years it would be worth the investment. I should have got a 5.4 and sounds like you should have too.

 

yeah its just straight pipes I was talking to him about putting the x pipe on it. Think he is going to get the edge evo in two weeks then if he is not happy with that its time to do a rebuild then super charger he said this will be interesting!!

 

Sounds like money is not a concern. Should have bought a 5.4. I have an 06 with 5.4, SCT, 40 series, s&b intake and it will move. My cousin has an 07 chevy with the hopped up 5.3 and after riding with me he said he doesnt even want to try and run me. Most everyone will tell you an intake does no good, however I love mine and I noticed a power gain. Maybe you need a programmer to fully utilize the intakes potential. Not sure about mileage gains on any of my upgrades because along with the mods comes a heavier foot. But I have gained a ton of power and have not lost any mileage, maybe even gained .5 to 1 mpg.

 

Yeah he should have bought a 5.4 but ran across the truck and it was a hell of a deal and I know that the 4.6 has the potential cause look at the stangs I know they are lighter but you can crank some serious power through them just wondering what yall perfer for biggest bang to the dollar!

 

Put a 2500 RPM stall speed Torque converter in it the 4.6 is not a low end torque eng like the 5.0 but a high rpm eng, I had a ford exp, with a v6 4.0 a 2500 rpm stall speed torque converter and 3.73 gears, it was a fun vehicle to drive

 

i know this aint my realm....but really? cant even spin them on gravel? my truck is a 97 4.6(less hp then your generation), 3.55s, and 31s. if i punch it from a stop, it'll spin them on dry roads. gravel, it'll never stop! unless hes exaggerating, theres a bigger problem here.

 

He isnt kidding I watched he held it to the floor and it barely spun maybe one revolution in 750 ft.