FORD 4.0 OHV to 4.O SOHC

cancinoj

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i will start from the end,. today was our first test drive of our CHUPAKABRAS, yes our class 3 ford explorer

finally, first test drive ,oh man,. this sohc engine is amazing,. i still can not believe it,. only modifications done are on the ecu by JuanCo,. well, still there it still needs to be fine tune i think, but so far i love it,. we are running that engine in front of a ford c4 transmission ( by JuanCo too) full manual with a ford 8.8 posi slip with 4.56 gears and 33" tires, right now the engine is set up to get the most out of it from 3000 rpms to 6500(we will need a high stall TQ), i don't know but my hand want it to shift at 4000rpm like we were used to with our old ohv engine, with this SOHC engine that was the bigining of true power, from 3000 to 6500 that thing revs awsome and the power that you feel is unbeliavable, i was amazed, i felt like 5000 rpms was the place to be, awsome hp and sound easy on the engine, now i know what "WOT" means, haha, the in car camera wasn't ready yet, hopefully for the next weekend or next test drive it will be ready so you can see what that engine does,. here are some pics,.

ps.. time to upgrade to a ford 9" on the rear,. :D





 

DSRacing

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Glad to see you are finding out about what some of us already know regarding the SOHC. Looks like you were having fun out there.

What's the stall speed on the TC you have now?
 

cancinoj

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Glad to see you are finding out about what some of us already know regarding the SOHC. Looks like you were having fun out there.

What's the stall speed on the TC you have now?
exactly really don't know, will have to ask juanco,. but i know for sure is a low stall, it was ok for the 4.0 ohv, that engine was stock from the ground up, it starts to move as soon as you hit the gas, so, what stall are you running or what's an ideal one for this engine?
 

jeff

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So what's a reliable SOHC build consist of for race use? Next question... what sort of HP/TQ numbers does a basic SOHC build produce at the crank?

Aloha
 

Captain Air Time

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So what's a reliable SOHC build consist of for race use? Next question... what sort of HP/TQ numbers does a basic SOHC build produce at the crank?

Aloha
depending on year, they are SAE rated at 200-210HP (265 tq?) or so, but according to several sources they are quite under rated. Believable, since thats a decent displacement, and it likes to rev...

Budget wise, I'd just run it stock, so whatever you pick one up for. Depending on age, you may want to go through it, but there's lots of low milers out there. New belt and hoses, and go worry about something else. Like any other motor, if you want to buy some more power, the sky's the limit. I'm fond of turbo's, myself :D

I'm currently trying to figure the best way to tailor my ECU, hopefully some info on that side of things will crop up in this thread, if not mine ;)
 

DSRacing

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exactly really don't know, will have to ask juanco,. but i know for sure is a low stall, it was ok for the 4.0 ohv, that engine was stock from the ground up, it starts to move as soon as you hit the gas, so, what stall are you running or what's an ideal one for this engine?
The SOHC has good torque, so it should be fairly quick off the line unless something has been done to the engine to move it's powerband into the higher RPM range. Our SOHC is stock and we run a C-4 with a 2200-2300 rpm stall speed. The engine runs consistently between 4500 to 6000 rpm during a race.

So what's a reliable SOHC build consist of for race use? Next question... what sort of HP/TQ numbers does a basic SOHC build produce at the crank?
Aloha
Depends what your definition of reliable is.;) In four years with the stock motor, all we have ever done to our engine is change the oil and filter after every race and occasionally change the spark plugs. As said in the previous post, the SOHC engine is rated by Ford at 210 hp and 245 lb·ft of torque. What's nice is when this engine gives up the ghost, I can pick one up for as little as $500.

There is rumor the SOHC will be phased out for the Duratec 35, which is currently in the 2009 models of the Ford Flex and a few other cars. It would be nice to have a plug and play 300 hp.

The official SAE certified engine output for the Duratec 35 is 265 hp and 250 lb·ft on 87 octane gas, but will exceed 300 hp once planned features such as gasoline direct injection (GDI), twin independent variable cam timing (TiVCT), and a variable runner length intake manifold are added.
 

cancinoj

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The SOHC has good torque, so it should be fairly quick off the line unless something has been done to the engine to move it's powerband into the higher RPM range. Our SOHC is stock and we run a C-4 with a 2200-2300 rpm stall speed. The engine runs consistently between 4500 to 6000 rpm during a race.
this engine is stock too, the ecu was modified by juanco,( we didn't test the explorer back then because we were working on the body and accesories wiring) we spoke with him today and we will meet him this week, so, for us this is something new, first time with this engine ever, so we really don't know what is normal and what isn't, i just know that from 3200 rpm and up that thing push the explorer like if it was hit from behind by a trophy truck haha, and as i said, we just swap this engine, the transmission and torque converter is the same we were using with the ohv engine,. that engine was stock and without a performance chip,

i don't know and still dont want to guess right now, but from iddle to 3200 rpms the engine missfires and not much power until it reach the 32oo, ,


ps,. i did this jump in first gear , this is a sequence of pics.
 

DSRacing

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i don't know and still dont want to guess right now, but from iddle to 3200 rpms the engine missfires and not much power until it reach the 32oo,
Obviously something's up if you have a misfire. The only issue we have with ours is when we get close to 6000 rpm, the engine will studder, similar to vehicles I've driven in the past with an electronic rev limiter. I'm sure Juan can fix the problem, I wouldn't recommend switching to a higher stall convertor just yet.
 

jeff

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Thanks guys!

A guy I know is in the 1st phase of a Ranger build and plans to run a SOHC motor. First race for the truck is the 1000 a little over 5 months away. I have no experience with these motors at all but it seems like as long as the basics are covered it should finish the race under power. Any tips or tricks that he needs to know? Any weird parts to look out for? Like a Grey vs. Black TFI module?

Aloha
 

Captain Air Time

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Obviously something's up if you have a misfire. The only issue we have with ours is when we get close to 6000 rpm, the engine will studder, similar to vehicles I've driven in the past with an electronic rev limiter. I'm sure Juan can fix the problem, I wouldn't recommend switching to a higher stall convertor just yet.
What ECU are you using? Ford, or stand alone EFI?

cancinoj, Great pics, that looks like a blast! Airing the Exploder is Good Times!
 

DSRacing

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Thanks guys!

A guy I know is in the 1st phase of a Ranger build and plans to run a SOHC motor. First race for the truck is the 1000 a little over 5 months away. I have no experience with these motors at all but it seems like as long as the basics are covered it should finish the race under power. Any tips or tricks that he needs to know? Any weird parts to look out for? Like a Grey vs. Black TFI module?

Aloha
The SOHC doesn't use a TFI module, it's a DIS system and doesn't use a distributor. All you have is the ECU, DIS module and the crankshaft sensor for the ignition.

What ECU are you using? Ford, or stand alone EFI?
We use a stock Ford ECU without a chip.
 

Captain Air Time

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We use a stock Ford ECU without a chip.
What did you use to taylor it to your needs? send out for a re-flash, or whatever (where?), or use a programer(which one?)? I have been unable to get a complete answer anywhere, so I'm on the verge of scrapping all the OEM harness and just going aftermarket. Then I know all I have to do is build some fuel rails and run it on an old fashioned return system. I'd rather have a plug and play, tuned and ready to do OEM setup for now. Unfortunately, frustration sets in, and that usually makes the Visa break OUT!
 

DSRacing

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What did you use to taylor it to your needs? send out for a re-flash, or whatever (where?), or use a programer(which one?)? I have been unable to get a complete answer anywhere, so I'm on the verge of scrapping all the OEM harness and just going aftermarket. Then I know all I have to do is build some fuel rails and run it on an old fashioned return system. I'd rather have a plug and play, tuned and ready to do OEM setup for now. Unfortunately, frustration sets in, and that usually makes the Visa break OUT!
The entire EFI system on the truck is OEM Ford, nothing has been done to the ECU. It took a little trial and error to find the right year and model ECU. Some years are better than others because of the changes in the programming by Ford over the years.
 

Captain Air Time

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The entire EFI system on the truck is OEM Ford, nothing has been done to the ECU. It took a little trial and error to find the right year and model ECU. Some years are better than others because of the changes in the programming by Ford over the years.
so you retained the speed limiter, all the cats and O2 sensors,PATS, returnless fuel system, etc? Looks like the speed indicator comes from the rear ABS ring/sensor as I can't find anything else that would give a signal.

Also, are you refering to a factory install, or a swap (like the thread)? Obviously, it would be simpler if everything was already done :)
 

DSRacing

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I should be more clear in my response, All the EFI electronics are OEM Ford. The older model engines had a return-style fuel rail, which we are using. We aren't running any catalytic convertors and the PATS system was disabled. This was a swap not a factory install.
 

Captain Air Time

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I should be more clear in my response, All the EFI electronics are OEM Ford. The older model engines had a return-style fuel rail, which we are using. We aren't running any catalytic convertors and the PATS system was disabled. This was a swap not a factory install.
Right, I believe only 96 or 97 came before the switch. So Did you use the older computer with the old fuel system, or do you just let the computer use the O2 sensors to work around the lower fuel pressure? or crank it up with an aftermarket regulator?
What about the after-cat o2 sensors? are they not causing problems with their way out of whack readings?

What did you use to disable the PATS?

Sorry for so many questions, but I'm having troube finding anyone to put them to, and here you are :D

Hopefully these are useful questions, and may help others who find this thread also. These motors are getting quite common with the inclusion of the Mustang donors, and I bet we see a lot more in new chassis'!
 

cancinoj

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so you retained the speed limiter, all the cats and O2 sensors,PATS, returnless fuel system, etc? Looks like the speed indicator comes from the rear ABS ring/sensor as I can't find anything else that would give a signal.

Also, are you refering to a factory install, or a swap (like the thread)? Obviously, it would be simpler if everything was already done :)
before we started with the swap from ohv to sohc i did some research and juanco was the place to ask, many guys want it to charge like 450 dlls to do the wiring,. i mean, we bought the 98 sohc engine on a junk yard for 400dlls complete with wiring harness and ecu, the only problem to start that engine is the ford PATS,. i did the wiring, i toke away everything and just left what was neccesary to turn on the engine,. the engine is already hoke up to the ecu, so, just need to connect to a switch the main relay or pcm relay, another hot wire that goes to the ecu, grounds and thats it,. that easy to wire that engine,. JUANCO disable everything about emissions, just left two O2 sensors, this engine comes with 4, so, the ecu that we had wasnt good, he gave us the codes for a good ecu's, he reprograms a chip to modify the ecu to his will, rpms to 6500, speed limiter up to the sky, fuel , timming advance , this engine came with returnless fuel system, we found a fuel rail with a fuel pressure regulator and he just set up the ecu to work at 45psi,

so, you need to use a chip in order to use this engine, otherwise will not turn on due to the f.. PATS system,.

as i said, the engine comes with three connectors,. well, all the engine wiring are connected directly to the ecu,. the other three, one goes to the power distribution box or fuse box, the other two goes to the O2 sensors, just be sure if you get the wiring harnes to have at least the main power distribution box, , from there, is easy to wire that.:D

ps, i don't know if i made my self clear, my english is not that good i think,. ha,. see yah.
 

cancinoj

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Right, I believe only 96 or 97 came before the switch. So Did you use the older computer with the old fuel system, or do you just let the computer use the O2 sensors to work around the lower fuel pressure? or crank it up with an aftermarket regulator?
What about the after-cat o2 sensors? are they not causing problems with their way out of whack readings?

What did you use to disable the PATS?

Sorry for so many questions, but I'm having troube finding anyone to put them to, and here you are :D

Hopefully these are useful questions, and may help others who find this thread also. These motors are getting quite common with the inclusion of the Mustang donors, and I bet we see a lot more in new chassis'!
by reprogramming the ecu you disable everything about emissions, just left 2 o2 sensors that needed when not going WOT,
pats also gets disable, that easy, single chip on the right ecu, not hard to find, and [ame="http://www.youtube.com/watch?v=lD2vPqTBDVI"]YouTube - CHUPAKABRAS FORD 4.0 SOHC ENGINE[/ame]
 

cancinoj

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Just to name a few things that can be done by reprograming the ford ecu

Change VIN
Remove VATS
Change RPM or speed limiters
Speed calibration for axle ratio or tire changes
POWER TUNE = spark timing and fuel maps customized for maximum performance
High or low octane programming
Lower fan turn-on temp settings
Modify shift curves for performance or towing
Modify shift pressures for firmer shifts, from mild to extreme
Modify TCC lockup speeds for performance or towing
Optimize transmission controls for high stall TC
Switch automatic to manual or vice versa
Compensate for displacement changes
Adjust for bigger fuel injectors
Adjust for larger throttle body
Compensate for cam changes for driveability and power
Delete emission functions and codes (EGR, AIR pump, CCP, O2s, etc.)
Program for MAFless operation = speed density mode
Delete various nuisances (SKIP SHIFT, traction control ,etc.)
Remove or add torque management
Delete other miscellaneous functions and trouble codes (A/C, oil level, etc.)
Nitrous, forced induction
Disable PATS and many more...
 
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