Follow along with the video below to see how to install our site as a web app on your home screen.
Note: This feature may not be available in some browsers.
Ford Explorer Community - Maintenance - Modifications - Performance Upgrades - Problem Solving - Off-Road - Street
Explorer Forum Covers the Explorer ST, Explorer Sport, Explorer Sport Trac, Lincoln Aviator, Mercury Mountaineer, Mazda Navajo, Ford Ranger, Mazda Pickups, and the Ford Aerostar
have a 94 ex 4.0 stock was wondering what exhaust systems are good. and what type of headers would fit i heard of hedmen headers r the good? ive read alot and saw that people put down the idea of headers on a 4.0 y is this how can headers b a bad idea. any input is good thanx
the stock SOHC manifolds are actually very good. Your money is better spent on the rest of the exhaust. When it comes to an exhaust you will get about 50 different answers. Although the consensus seems to be that the 4.0 needs at least 2 1/2" exhaust pipes that are free flowing. Most of the differences in cat back systems are more in the sound than the actual power differences. You will need to figure out the tone that you want. If your looking for more power you may want to look into an under drive pulley it seems to provide a good bang/buck enhancement.
Welcome to the forum...
edit: wait a minute which 4.0 do you have? :scratch:
His truck is listed as a 94, its got the OHV motor. I have not looked into this much yet. I understand that real gains come from longtube headers. I guess headers would help a little, but I have no experience with them on a 4.0.
Also remember with more air out you must get more air in for any real gains. You can actually hurt performance by only doing one modification. I have heard of more then one port/polish job that looked great but hurt power after installed. Keep in mind also that your 94 has dual O2 sensors. You will need to get headers that address this, or weld in a bung for the second sensor. 91-92s had only one O2.
Try searching the modified 91-94 threads, you may find more info there.
The stock manifolds flow quite well in the useful RPM range of the OHV motor. Headers are good if you throw on a lot of other mods like a performance cam and top end parts to go with it. Headers are fairly expensive ($300+), at least the good ones. The cheap mild steel headers (pacesetter, hedman, etc.) seem inexpensive, but eventually rust away.
You can get more improvements on the OHV by taking care of known issues (spark plugs, plug wires, rocker arms/pushrods, etc.) and basic intake/exhuast mods like a K&N air filter/modified stock air box or KKM intake kit, and a good exhaust (Dynomax makes a Super Turbo kit if you want a deep tone and good flow, Flowmaster makes a kit if you just want loud), or you can even just modify the exisiting exhaust by throwing on a new muffler.
I have had the headman headers since 2002 and they have not rusted through yet. Ugly they may be but they perform. I you get the Headman, get used to replacing the collector gasket and possibley the header gasket often. I'd save and buy the JBA. They will seal better and last longer. I had to smooth the flange surface on my headers and use larger head bolts for my Headmans.
When I bought my Headman headers, they were like $190. You can get them from Summitracing.com for $262.95 now. The JBA stainless steel uncoated headers are $659.95. I think it is worth the extra $397 for the JBA's for fit and finish.
Yes they will respond better without other mods. At the time, all I had was the KKM. Adding other mods will only assist to make it better. GOOD LUCK!
When I first installed it I didn't notice anything, believe it or not, when I put it on, I did not disconnect the battery. 6 months later when I was puttign a CAI on my Durango, I read that in the install procedures to disconnect the battery so the computer could remap the new parameters. I immediately removed the negative terminal of the EX for a few minutes and then went for a drive. It was a night and day difference, even after driving it for 6 months.
After I installed the MAF, I also noted a big improvement in power all the way to redline. Just throwing that in there!
IMO i have not heard a 4.0 sound good... maybe its the speakers on my computer or the sound quality of youtube but they all sound raspy, and like one bet wet fart...or maybe im used to slp exhaust on my v8 camaro
I have a Raven muffler on my Ex. It makes the Ex sound good but nowhere near GM V8 good. Midas used to sell them but somebody bought them out. They flow better than the Flowmaster and have a better, more rumbling sound. Sorry, no sound clip.
