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how to get MORE power

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Ok so i have a 1991 f150 with a fuel injected 302/5.0 with a 5 speed manual, with 4-wheel drive and a six inch lift. i was wondering how i could get more power that doesn't cost an arm and a leg. 200 horsepower doesn't cut it when towing up hills. any ideas?

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If you have bigger than stock tires, you can start by re-gearing.

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less restrictive exhaust, gutting the cat and a flowmaster 40 should do the trick, works on my truck. a programmer will help but on paper they don't promise too much gain for the price tags.

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You didnt say what size tires.......

X2 regear. It aint cheap, but thats what your problem is. Doing the exhaust or what ever is just a bandaid IF you have bigger tires without regearing.

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Don't mess with the cat. They're expensive to replace and more and more states are checking the older vehicles' cats.

My experience is there's free horsepower under the hood if you know where to look for it. Stock air intakes are very restrictive since they're intended to reduce noise, which often reduces power.

Take all the resonator boxes off the air intake, block the holes off with anything that will fit. I often find the inside ring of spray paint caps will fit in if you're creative. If your truck runs better this way, you're off to a good start. If it doesn't, put them back in selectively, I'd start with the smallest ones first, until it does run better.

Next, find a K&N air filter on eBay, not the drop-in kind if you can avoid it, you'll need to make your own air box, the old one is probably a square box and forces the air to make an S turn to get to the MAS.

Measure the best round piece of pipe you can find on the air box side of the MAS, you'll need to buy a K&N cone style filter that will fit.

If you can't find one, you'll need to make a plate to bolt up to the factory bolts on the MAS and have a 3" piece of exhaust tubing welded on, 2" long should be enough and then some.

Now that you've got the filter on the MAS, you'll need to add a heat sheild, or better yet, build a new air box that draws cold air in from somewhere, I personally like to do it at the windsheild, but sometimes this isn't possible, because of silly components like brake masters. If you can't get in there, draw it in from the fender, cut a couple of 2" holes with a hole saw, use some of the metal left over from the air box to make a duct. An easy (but not pretty) way to do this is wrap the metal around a 2X4. It will end up being slightly oversized so it will mate up with your 2" holes quite well. Use anything you can to insulate the box from heat and seal it up pretty well.

Aside from that, I agree with the others, you'll need to change your gearing if you changed your tires.

A cheaper way is to install smaller tires, there's a lot of rotating mass in really tall tires, some of the swampers/mudders I've handed are almost a hundred pounds.

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With a 6" lift, I'm guessing you're running 35" tires.

If you're not willing to put the truck back to stock height & tire size, then you need to re-gear BOTH differentials (I'm assuming its 4x4).

After that, the only cheap thing you could do would be to open up the exhaust, but it isn't going to make a huge difference.

Beyond that its all pretty expensive.

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With a 6" lift, I'm guessing you're running 35" tires.

If you're not willing to put the truck back to stock height & tire size, then you need to re-gear BOTH differentials (I'm assuming its 4x4).

After that, the only cheap thing you could do would be to open up the exhaust, but it isn't going to make a huge difference.

Beyond that its all pretty expensive.

re-gearing both differentials is spendy too. Its a difficult job that is easy to screw up.

Since gas mileage is probably pretty poor anyway, how about a 460 transplant :p:ride:

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re-gearing both differentials is spendy too. Its a difficult job that is easy to screw up.

True. But like somebody said before, anything else is really just a band-aid fix until the real problem is addressed.

My brother-in-law had a '91 F250 with a 351, he ran 35" tires and the stock 3.55 rear end. My stock 300 6-popper would run circles around him if we were towing our RV's.

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gas and power dont mix unless you boost it

re gear, intake, exhaust, cams all exspensive but it cost that when its NA

pay to play unfortunatly

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im going to recommend at least 4.10's if not 4.56's , i run 4.10's with 35" tires and a 350 but then again my first gear is 7:1, since you have a od tranny you might as well go for 4.56's it will feel like you have added 100hp if your going from say 3.55. if i had a od tranny i would run 4.56's .

my dad had a 94 5.0 f150 , gutting the cats opened that stupid truck up more then i have ever seen a gutted cat open up a truck . drive-ability was the main improvement but it just generally sounded better and had more power .

however were i live it really doesn't matter one bit if you have a catalytic converter or not so most people don't run them . you could always just remove the cat and put in a piece of pipe if you get caught just put it back in .

intake restrictions , some vehicles benefit from removing them some don't .

perhaps another idea is just to buy complete axles from a junk yard , the diffs in that truck are a dime a dozen you should be able to pick them up for a couple hundred bucks and even sell yours for the same amount in a buy&sell just find a f150 that had a tow package check the tag on the diff cover should be 4.10's .

its what i would do if i didn't know how to set up rear ends . its really not that hard just time consuming and you need some special tools . at 17 i would of done a re-gear in shop class , don't you have automotive ?

the big questions here are what gears do you currently have ? it will say on a little tag on your differential . and what size tires are you running ?

camshaft , intake , exhaust . those are the cheapest power adders after that its alluminum heads and then stroker .

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