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Discussion Starter · #1 ·
Help me out here, I'm engine retarded. I have a 96 Explorer Sport. I'm pretty sure my engine is the 4.0L OHV @ 160hp. Ford also makes an engine that is 4.0L SOHC @ 210hp. Both are V-6.



Both have 6 cylinders.....both are 4.0L.....WHY DOES THE SOHC HAVE 50 MORE HP??!?!?!!?



I have always been a little disapointed with the performance of my Explorer and this little tid-bit got on my nerves.



To make it all worse, the OHV and SOHC seem to get the same gas milage (according to msn autos).....what the &$%#
 

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Im just as engine retarded as you. I guess for some reason having an over head cam increases power.
 

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I have no idea either, but I do know that the OHC has a higher compression ratio than the OHV.
:



Currently, I am not an engine expert, but I am very interested to know also.
 

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Discussion Starter · #4 ·
Ok, so I've been doing my homework and reading up. It might have helped if I knew what OHV and SOHC ment first....



OHV= Overhead Valve

SOHC= Single Overhead Cam

DOHC= Dual Overhead Cam



Ok....its a V-6 right? So that means that the cylinders are in a "V" configuration (right?). In a SOHC engine, this means that there are actually 2 camshafts...one above each row of cylinders. That camshaft controls the opening and closing of the exhaust and fuel valves. In a DOHC there are seperate camshafts for the exhaust and fuel.



From what I've found...OHV is one of 2 things. Either its just another name for SOHC, or its a system where there is 1 camshaft and its inside the engine block, not in the heads. It uses rods that connect up into the valves to control them.



All in all I'm pretty much still confused. But even more frustrated cause it seems that the OHV is nothing new or great unless you are trying to make an engine that isn't as efficent as one with mulitble camshafts and much cheaper. The only good thing is it might be easier maintence wise.



BTW, howstuffworks.com is awesome if you are like me and had no idea what the hell a camshaft is/does.
 

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The OHV is a heck of alot more reliable that the earlier SOHC's in EX's. They had severe timing chain problems and recalls, but I believe that has been worked out in later models. The timing chain would break and cause piston slap, which (I think) is when the timing gets off and the piston hits a valve in the head.



I think that the OHV uses a single cam in the block, and has pushrods that control the heads, so I believe you are right.
 

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Tido, you do have an OHV engine in your Explorer.



99SportX, the early SOHC motors had problems with them. Now they have all the bugs worked out of them. There are people on EF that have over 100k on their SOHC without any problems. I think I heard of one person that had over 200k on theirs.



The cam for the OHV is in the block and has push-rods to control everything. The bad thing about OHV is the push-rods can break. The SOHC eliminates that problem by have the cams control the valves without the help of push-rods. I think the main reason for the HP bump is the higher compression though.
 

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99SportX, the early SOHC motors had problems with them. ?Now they have all the bugs worked out of them. ?


The OHV is a heck of alot more reliable that the earlier SOHC's in EX's. They had severe timing chain problems and recalls, but I believe that has been worked out in later models. The timing chain would break and cause piston slap, which (I think) is when the timing gets off and the piston hits a valve in the head. ?


There are times I wish I had the SOHC
 

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A good mod for the OHV (what I have) is to get a new camshaft that has larger cams. This will open the valves wider to get more fuel/air in quicker and exhaust out quicker (and easier). Roller rockers help to actuate the movement better and a good port & polish will help gases and mixtures turn corners more efficiently and flow faster. All of these little things add up and with enough $$$ you will have a stronger engine than the SOHC. The single camshaft is actually a plus because all of your timing is controlled by one shaft. You can always upgrade your push rods to defend agaist "blowing a rod". I would like to know what can be done to increase compression without involving too many other processes. Anyone know any tricks?
 

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A good mod for the OHV (what I have) is to get a new camshaft that has larger cams. ?This will open the valves wider to get more fuel/air in quicker and exhaust out quicker (and easier). ?Roller rockers help to actuate the movement better and a good port & polish will help gases and mixtures turn corners more efficiently and flow faster. ?All of these little things add up and with enough $$$ you will have a stronger engine than the SOHC. ?The single camshaft is actually a plus because all of your timing is controlled by one shaft. ?You can always upgrade your push rods to defend agaist "blowing a rod". ?I would like to know what can be done to increase compression without involving too many other processes. ?Anyone know any tricks?


Where did you get the cam? How much did it cost? Also, where do you buy roller rockers for the ohv. I have never seen any in catalogs.
 

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This is in another thread I think as well. For those with the 4.0L OHV model that want to do it and can have the things shipped to them
check out the website I pasted in another thread on here somewhere. They can take care of you. Remember it is costly
I have been wanting to do this for some time now but getting the heads here is next to impossible. I may do a cam and such. Oh and it isn't different cams it's lobes.
 

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I haven't actually done this stuff. I'm just speaking in general given the available parts. I don't know for sure if these parts are available for this motor. You could ask Crane Cams @ cranecams.com. You'll need the current part number. Anyone know what C.I. displacement is?
 

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BC Power it really is easy the old OHV is a tough engine, there are guys pushing 300 thousand plus on original engines with almost no compression loss at all. As for CI that is cubic inches hence the size of the 4.0 some sites say it is a 245 others say 240. Others say it is 244, which is about right. I don't recall the compression ratio off hand but it can be found pretty simply if you search for it.



I know the guy with the 8second splash has a 4.0L OHV in his so power can be had. As far as parts the only real source left is www.rangerpowersports.com

They have the same vin X engines that we do for the old OHV. I don't want to advertise so I can ask Doug and a couple other guys over there to join up here and see if Rob can give them a 'Ranger' section. I don't post much just been on the look out for that BBK instacharger and Kodiak was selling his but we had a death in the wife's family so I havent been on much lately.



Also the parts numbers you are looking for as far as cams and such can be found on that site. I do not remember the manufacturer of them. For those interested those guys have been down the road with the 4.0 for years working it for power so that is a good source pretty much the only source.



Oh and so you SOHC guys don't feel left out they are starting a project one of those so they will try and test the parts out and see the outcome, Black Magic should be sneaking around there for info
 

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OHV compression ratio is 9.0:1.
 

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Hello guys, you should all try to get the SOHC, and toss the old OHV V6. For a keeper, the cost is well worth it. My 93 Explorer pings when warm, even with a good tuneup.

The SOHC is a more efficient combustion system, thus it is capable of more compression. It can be more fuel efficient, and more powerful, in a fair comparison to the OHV 4.0.

The 4 speed automatic A4LD is an inherently weak unit. It was derived from a four cylinder Thunderbird(3400lbs.) application. The SOHC has a 5 speed transmission, which also gives the vehicle an edge. It should be much more reliable, as it was designed for these heavy vehicles.



I am looking to change my chassis to a SOHC 4x4 chassis, for normal usage.



Some of you may want more than the stock power, and may be thinking of a supercharger. The higher compression of the SOHC will limit the amount of boost that can be used. It will also mean that preignition(pinging) will be more likely.



I know that there are kits for both now. The SOHC will be a more reliable design. If you want significant gains with a supercharger, then you should lower the compression to 8.5, or 9.0 to one.

This compression issue is the same with the Mustang Cobra 4.6 engines prior to 2003. They have a higher compression, and weaker bottom end parts than the 2003+ engines.

Good luck all,

CDW
 

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I'v got an SOHC, I'm pretty pleased with the proformance, I would like to do more to it in the future but for now... it's stock with some kind of thingy... I'd have to look at the sticker again, haha Sorry. I baught my Explorer on Saturday, October 22nd 2005, at 2:24 P.M. ( Great memory right? ) it had 85,000 miles on it, since then we have put 10,000 miles on it... Most of that was the thrill of a brand spankin used car! But anywayz... It's VERY clean, needs a few cosmetic things... such as a left Tail Light, has a small crack in in, and water gets in it every time we wash the truck, and in winter. some IDIOT... threw a cigarett and it landed on the truck right under the driver side wiper, It's MELTED!! A** HOLES! and then... somebody eles threw ANOTHER one and landed on the pain... BURN!!! So sad! we paid $8,000 CASH! and its worth $11,000..Awesome!
 

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And another great deal, this one is to great not to tell about! My brother just got a '99 Toyota 4Runner for $8,000 cash... It's worth $13,500!!!!!! and its only got about 400 miles on a rebuilt motor, the reason the old motor blew is because the guy that had it before was doing some work on it, and forgot to put some important cap on, and KABLOOY! ...Heres the pic of his 4runner, and his Baby ( Trans Am ) the white 4Runner you see up there with the rest up my pics, if my brothers wifes truck.
 

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Nice vehicles with great prices for all of them.




Your cracked taillight and melted wiper cowl are easily remedied. Unfortunately the paint isn't but you should see what it would take to repair it.
 

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Thanks, I dont think any of that is a big deal right now but sooner or later I'll replace them. Thanks for the reply:-D
 
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