Best bolt ons for the 4.0L OHV? | Ford Explorer Forums - Serious Explorations

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Best bolt ons for the 4.0L OHV?

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Active Member
December 22, 2010
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City, State
Seal Beach
Year, Model & Trim Level
1993 Exp Sport 5-spd 4x4
Hey all. I'vd seena. Lot of threads on DIY air intakes and throttle bodies but little corraborating evidence of actual gains.

What are the most potent bolt ons available for the 4.0L.

I've got the 5-speed manual with my 4.0L so the automatic is a nonissue.

I am planning on a JET Performance module, a higher flow intake inlet tube and airbox assembly and adding the highest flow, lowest noise muffler I can find. I'm thinking Borla HUSH.

My overall goal is a slight bump in power and a tastefully modified engine.

What are the other proven bolt-ons for the 4.0L and who's the vendor? Thanks!

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Forget the Jet module,I researched it and the consensus is it's overpriced junk.My 94 got a set of plugs,wires a KKM intake and a turbo muffler.

Huge improvement with out wasting the money on the Jet.You have to remember that these motors simply don't make tons of power in stock form.

Try the easy stuff I did and you will be quite pleased with the change....if you have a decent engine that's not worn out.:D

Total cost..about $200

Most turbo mufflers are just junk that are made to just make more noise without improving flow at all.... heck, most "turbo" mufflers actually restrict exhaust flow even.... Many aftermarket performance mufflers do improve exhaust flow. Borla makes good mufflers, but you won't see much out of just a muffler. If you added headers, high flow cat, full exhaust, throttle body improvement, good intake system..... they start having a cumulative effect. A different cam and a little machining on the head, then you start seeing some cool stuff happen.

I picked up a KKM intake because I was tired of arguing with people who insist an air filter adds eleventy bazillion horsepower..... Waste of money... I have been switching it back and forth with my stock filter box and making a few long drives to gauge fuel economy increase.... I see about .2 mpg with the KKM. Throttle response? Well, the throttle does the same thing it did before... when I press the noise pedal, the truck goes faster.... Anyone who ever mentions throttle response when talking about an air filter is clearly retarded. Horsepower? Well.... I will dyno it this summer if I can still get dyno time... I expect to see between 3 and 5 horsepower somewhere above 3000 rpms.... Peak might move north a hundred RPMs, but I doubt I will see much more than 1 or 2 horsepower improvement at peak. Driving it, I am assuming the dyno results will be the same as any other car with a cold air intake. The real power of this intake would be supporting other modifications.

Plugs and wires? Well, they are good for a TON of horsepower and torque as well as a huge improvement in fuel economy.... if you have bad plugs and wires in your vehicle.

The Jet chip... idk... I have never heard anything good about it.... most mail order chips aren't very good anyways. It is best to just get a blank chip and get to a dyno shop and get a custom tune. ~$500 and quite a bit of bang for your buck. Do it after you have done all of your other major modification.

You want some good modifications? Electric fan, even though the fan clutch mostly disconnects the fan when it is not needed, you will notice, it still is spinning some anyways.... there are small losses. I can't recall if there are any underdrive pulleys available for a first gen.... I would think there are. Honestly though... these engines aren't really capable of doing a lot stock or with just a couple bolt-ons... they are built for longevity and reliability. If you want more power in an explorer, get an SOHC.

Check out Creager's 4.0 build. it is a sticky in this forum. he did a lot of work to his motor. after he finished and had driven his new beast around a bit (before he disappeared from the face of the earth) he said he would have rather just swapped in a 5.0.

And I agree, gear swap is the best bang for your buck.

KKM Tru-rev intake
Dynomax Super Turbo cat-back (or use the Dynomax pipes and throw on your choice of muffler in between the cat and rear pipe)
Magnecor wires
NEW OE Motorcraft plugs (if currently using something else)
OE Throttle body mod
Accelerator cable zip tie mod (if needed for WOT)
MAF sensor cleaning
Basic maintenance (tire pressure, fluids checked, good brakes, etc.)

Just about all you need for a pretty zippy Explorer with minimal spending.

Hello everyone i`m new to the site and i have a few questions, Does the KKM Intake affect the mass air metter at all? What is the OE throtle body mod? and what is the Accelerator cable zip tie mod?

Hey, I have the answers to those. The zip tie mod only benefits at models and simply takes the slack out of the throttle cable- it has no real effect on performance besides that. The oe throttle body mod is having your oe throttle body ported and polished, I have one. The KKM intake is a waste of your money.
The best intake mod is the large diameter maf to tb tube from profab listed for 4.0l ranger.

The screamin demon coil i have and jet chip have also been big plusses.
My exp is for sale now that its friggin built.. 5 k obo w new 5 speed fresh clutch and motorcraft clutch master but apparently i'm not allowed to post in the gorram classifieds.

like its said here before if your looking for lots of power get a 5.0...unless you plan on spending lots and lots of $$$..but hey i gotta say for the OHV its a pretty tough all you gotta do is pay the fee to become an elite and then you can post to sell your truck...i think the 20 is worth making what you will make if you get a sell on here..just my .02 cents:D:D

As you can see, these mods really don't buy that much actual hp but they do make a difference. Cumulatively all of it makes a night and day impact- forgive the whole post above but I think it adequately explains what does what.

awesome explorer. the first gen explorer was a few shortcomings short of being a jeep or better. this explo is reminiscent of a jeep and its good to see that. though i think we are all a bit bitter at cherokees (or at least their reputation) ! we know our explorers can meet or exceed jeep performance! well done. good luck in selling im sure it will make someone very satisfied.

p.s. did you say this explorer came with a solid front axle stock?


Nice X, I like the headlights. Your X is the only other one I've seen with them besides mine:cool:.
Looks like you may have some tire clearance issues when flexing though.....lift.....
Sorry but, I'm not buying the solid front axle stock thing.....never my knowledge all 1st gen 4x4's came with the TTB Dana 35.

All in all very nice truck though, really diggin' the wheels:chug:cheers!

Just looks like a stock explorer with some paint and a bunch of bolt ons.

And no, it didn't come with a solid axle.

I was told it is a solid front axle and sports a dana 10bolt of some sort. I may be misinformed

I call BS on the horsepower and mileage gains.

Performance Tune Up with High Performance Plugs
Screamin' Demon High-Performance Ignition Coil (+1-3mpg and several HP)
JET Performance ECU Chip (Good for 1-3 MPG and +13RWHP on a stock motor)
Pro-Fab 4.0L Airbox-To-Throttle Body Intake Tube (+10 rwhp)

Starting with the most obvious question, where is your dyno slip? Next, what is a "performance tune up"? Is that where you change plugs wearing a racing speedo? In what insane world do you expect to make people believe changing coil packs gave you more horsepower and mileage, unless of course your stock one was bad?

You have a darn good looking Explorer. Sell it using that, not using some imaginary 30 horsepower and 6 mpg. You also did a darn good job of writing an ad for it, but when you lie, it is not good.

I've got more of those bolt-ons than you, and I won't claim any retarded numbers like 30 horsepower and 6mpg. You have a very nice truck, but the BS in your ad is just overwhelming.

The HP figures for the JET performance chip are actual dyno results from Jess Pranskus, tech over at Jet Performance for what the chip is supposed to deliver. I can cite the dyno sheet if need be. Screamin Demon coil is only good for a handful of HP and the figures from the pro-fab intake are what I was told the intake tube is supposed to be good for. It does get much better mileage than it did beforehand, my wallet and fuel expenses since modifications attest to that. Again, gains are cumulative and complimented by other components. It is without question a much more powerful truck as a result. I have not dyno'd it because I don't see the need to and what I wrote was correct as far as I know. How do you know a JET Performance chip is *not* good for those figures? I'd like to see your dyno sheet proving JET wrong.

I'm not trying to pull the wool over anyone's eyes here, just what everything is supposed to
be. Given how restrictive the factory intake tube is and the difference in response, 10 hp doesn't seem all that unreasonable, particularly in conjunction with the rest of the modified intake tract. Notice I did not quote gains for the drop in filter or the ported/halfshafted tb. Considering I bought my coil and tb from a reputable tuner's personal vehicle, I don't see why a higher voltage coil would not result in any gains.

I don't see how widening the plug gap and increased voltage would not naturally increase output and by handful of HP I'm talking 1-3hp. I know firsthand that small changes such as a tb spacer can result in 1 rwhp and +7 rwtq in other Ford applications.

Performance tune up means I used quality HD components rather than just whatever stock was, ie, to increase performance.

Lord, you lot are harsh. It's no wonder I don't post that often. I'm glad I am leaving the Exp community. I put everything down to the best of my knowledge.

Direct quote from JET:

"PN 89314- +13RWHP@3200rpm and +11 RWTQ@2800rpm."
Where are your dyno sheets disproving this?

Plus, search Screamin Demon coil on any of the Ranger forums, a number of threads confirm HP and mpg gains. I am attempting to contact Performance Distributors to confirm directly, but the line is busy. (901) 396 5782 re: PN 31738

Make sure you can back it up before you call it imaginary. While I may have been wrong on the solid axle, I stand by the figures I quoted. 13+10+3 adds up to an overall estimated 26hp, not 30. I also confirmed with a coworker who used to own a minitruck shop and sold speed parts and did see those kinds of gains on their dyno, it isn't at all out of line with reality.

Re: solid axle- it appears I was misinformed on that particular point as I was under the impression that it was. It looked like one to me, but this is my first 4x4. I will revise the listing.

I'd like to see hard concrete numbers via a dyno of one with a chip and without.. The claims by the manufacturer are somewhat erratic across other forums.

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this site is very mild compared to most. post your ad on pirate 4x4 and watch your post turn into a 20 pager. The reason your catching crap is because you came onto a site with some people that have more knowledge on these applications than the people who put them together. Your "dana 10 bolt" spews your misconcepted knowledge and will deter anyone who is into the 4x4 scene away from your truck. A "dana 10 bolt" is not a commonly used term for the simple fact that there are many dana diffs that use 10 bolts to hold their covers on. it could be a dana 30 or a dana 80 or a GM 10 bolt from the way you have it worded. or maybe even a stock "non solid" dana 35 ttb. It's more the used car salesman type wording that your using than anything. Theirs nothing wrong with not knowing certain specs but not knowing and trying to sell the vehicle on misconceptions you have to expect to get some comments.

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