Originally Posted by The Great Scaper
O.K. I have a 06 fx4 auto extended cab with 4.0 ltr. milage 3,500 k.m.
I want to increase my power. Budget isn't a huge issue so here is my thoughts and questions.
- a larger exhaust? a single 21/2 inch exhaust...muffler?....dual 21/4 out?
- headers. which ones are available? does this affect what exhaust I should go with?
- a larger throttle body? is this worth while? how does this affect my choises above?
- a k&n filter. I know some of you don't like them, I am a huge fan so I am getting one.
- underdrive pullies
- chip....I am not sure if I want to do this or not....any helping feed back?
- any other suggestions?
I am going to take my truck to a dyno tune before I do all the mods. Then after instalation of everything I am going to see the difference. I will share with you my numbers. Thanks guys!!!
To answer your questions-
The best value on exhaust right now is the roush/slp kit on clearance at Hillbanks. $165 shipped for a single in/dual out kit.
The only headers available are JBA, although I think Gibson is coming to market with them. The JBA's are stout so you don't get the leakage and problems from thinner flanged headers. The only option would be ceramic coated vs chrome. I would get ceramic if the budget allowed it.
I am not sure a throttle body is on the market. I could be wrong on this. if the new Rangers have "drive by wire", then the 4.0 Mustang should fit it. if there's not one for the Mustang yet, there will be.
K&N is a reliable and proven brand. It's one of the few that are on the market for the 04+ Rangers. It will be noisier than a sealed box system.
Pulleys- Bob's comment about $265 for 4hp is off base unless everything else is quantified. I would have to see HP gains for a $400 chip or Hp gains for a $500 header or HP gains for a $130 E-fan before I agree. Even so, cost vs reward is an individual decision. The other point is the gain (whether 4, 8, 0r 12) is gonna be over the entire rpm band. That is generally not true with other mods. If a $300 exhaust loses 2hp through 3000 rpm and gains 5 from 300-4000 then gains 10 from 4000+ a better value? You have to look at the total picture.
Chip/tuner- definately needs to be fit into the equation. Go for a tuner over the chip. It should allow other functions that can help defray the cost like a code reader, code clearing, odometer adjustments for tire size changes and gear changes. I would get more info on where it fits in. If you have to get new tunes after intake, exhaust, etc it would be better to wait until after these mods. I don't know the answer on what mods need changes in the tune so I could be offbase on this.
Cats- look under the truck and start counting how many you have. Bring a kleenex because you may need to wipe some tears off your eyes. if anyone has a legal solution to this I am all ears.
There is also diminishing returns. A header will give x HP and an exhaust will give z hp but the two will not add up to x+z, mainly because they are helping to in the same area (air out). Air intake plus throttle body would be grouped together in the same way (air in). I would do a sweep of each area then fill in voids as money becomes available. If you have the funds to get it all done, you'll have a topnotch truck.
There are 3 things on the list that do nothing but add HP- the tuner, throttle body and the pulleys. Everything else will change the sound of the engine. Some love it but you can get to the point where you can't hold a conversation while driving. Having quiet mods has it's benefits for some.
Weight is directly related to HP. You can add intake/exhaust/pulley then go to 33" tires and you are back to stock speeds. I know someone this happened to. You can regear the rearend to gain a lot of it back but the extra weight will be a factor. Some are lucky to have their 'go mods' keep pace with your "slow mods". Besides wheels, it would include tool boxes, sound systems, brush guards, sub boxes, etc.
Other options include:
e-fan (will add some efficiency to the total package).
Camshaft- will move the power band up higher so it's not fading out before redline. Not a two hour install though.
Rockers- I haven't researched it for a 4.0, but this is basically a poor mans camshaft and is a fairly easy install. It lifts the valves higher so more air can get in or out.
Higher stall torque convertor- This would help tremendously at takeoff. Your HP at 1000 rpm is about 50HP, your HP at 3000 RPM is about 125HP. Logic dictates that the higher the rpm you leave at, the higher the rate of acceleration. My 60ft time at the track went from a 2.4 secs to a 2.07 secs in an s-10 I have. I contribute a lot to the higher stall convertor.
Traction- HP is nothing if you can't utilize it. Get a set of James duff traction bars. They are around $100 new. i would put this on your short list. It doesn't add HP, it allows you to use what you have.
Heads- another $$ heavy mod and thanks to the mustang having the same engine they are available now.
Supercharger- if you want to get past a bunch of 4-10 hp mods and get the most HP now, go with a supercharger. You generally get a 50% increase which should be in the range off 100HP. $4,000 is not bad. You would spend more than that on every other mod and probably not get close to that number. There's a guy here that is set up to sell the explorer express supercharger. I think it's Nickstersvt (apologies if I got the name wrong)
Keeping stuff fresh- let your spark plugs go too long and the gap will punch out so far that you will lose a percentage of the spark. No spark means the gas gets burnt in the cats, which is like running on 7 cylinders each time one doesn't fire. In the range of 40-50,000 miles shuld do it. The motorcraft plugs with the fine wire platinum is as good as any plug I have used.
If I get an extra $65 I'll get back to the dyno. My only two runs were stock at 180 HP and crank pulley at 188. My current set up is an e-fan, underdrive pullies (3 piece), roush slp/exhaust, and K&N intake. Headers and tuner are next on my short list. All in good time.
Good luck and have fun with the new truck.