2.9 to 4.0 engine

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grumpy old man

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Looking to upgrade an 89 Eddie Bauer BII to the 4.0. Looking on insurance salvage for a donor truck and discovered that sometime around 1993 they changed from the enlarged 2.9 to a 4.0 SOHC. Obviously the cammer would have more potential than the earlier cam in block but what changes were made with the newer engine and what additional work/ engineering would be necessary for the swap. I will be overhauling the engine before it goes in, probably doing a cam change maybe some headwork depending on what the ports look like.

Not looking for the pros and cons just interested in how much extra work will be required to install the cammer.
 

L\Bronco

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Looking to upgrade an 89 Eddie Bauer BII to the 4.0. Looking on insurance salvage for a donor truck and discovered that sometime around 1993 they changed from the enlarged 2.9 to a 4.0 SOHC. Obviously the cammer would have more potential than the earlier cam in block but what changes were made with the newer engine and what additional work/ engineering would be necessary for the swap. I will be overhauling the engine before it goes in, probably doing a cam change maybe some headwork depending on what the ports look like.

Not looking for the pros and cons just interested in how much extra work will be required to install the cammer.
Hey Grumpy
The SOHC 4.0L had some issues (do some research) The Early ones made a little less power, but will be an easier swap. Either one is do-able and will give good results.
I have a build thread in here on my 79\5.4 lightning swap you should look at.
There are countless things to consider and be aware of. Remember every action has an equal and opposite reaction.
Stay early enough that you wont have to contend with PATs.(anti theft) The pre OBD2 systems are difficult to tune, usually requiring a piggy back module, so be careful how far you go with performance upgrades. (The PCM will get crankier as you increase the volumetric efficiency.)
It will be awesome when its done. (Still a bit bummed that we won't get to the bottom of the issue with the 2.9.) (Just for sh-ts and giggles, did you ever pull the vac line off of the fuel pressure regulator and look for fuel at the vacuum port?)

Ill be watching for reports on the swap
Cheers
 
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grumpy old man

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I believe you meant that the OHV is an easier swap. What I have found is that the SOHC engine is much larger physically and will require surgery to fit in the hole. Maybe stronger coffee?

The fuel regulator is clean only has a couple of hundred miles on it. Before you say it I have long since learned that new does not necessarily mean good. I have started putting the old parts back on it, started with the O2 sensor this morning and the high cold idle now starts to come down almost immediately. I did compare the new motorcraft map sensor with the original, totally different part number, that's next. The 89 emissions manual gives no spec on the MAP.

I have been researching the engine swap. Found that to make a legal swap I need to put in the engine AND trans from the donor vehicle. Also need the speed sensor? in the rear end which if I have a complete donor truck should cure the issue. Do you know if B2 and ranger all have the same gear ratio or do I need to be careful of that?

I have decided to stick with the OHV to eliminate a lot of under hood surgery, maybe a cam change when I do the engine. If it were for me I would use the cammer because of increased potential but it is not. My granddaughter does not need and would not know what to do with the extra horsepower so go for the easy.

I am trying to go post OBD1 what model year did the PAT's start. If I do manage to get a PAT's donor couldn't I just get one of the aftermarket modules to turn it off? I want OBD2 and don't want PAT's, what are my year ranges? This swap probably will not happen until summer 25. I need to find my donor vehicle and go through the engine and trans so everything is fresh. Too much to do as I need it running at end of summer.

The CEL 41 resets as soon as you shut it off so if I can get it in emissions range long enough to pass smog without triggering the 41 I can always put a piece of tape over the light.
 

L\Bronco

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1)Yes, sorry, not enough coffee. Cam in block would be easier, is what I meant.
2) the map sensor signal in those is a 5v signal that is a variable frequency that should be 150-153hz koeo (depending on baro pressure at the time of test) so good luck. If you have the means to measure it, it will drop as the vac gets better all the way to 80 to 90hz at good idle.

3) There were many gear ratios available in those, its usually stamped into a tin tag on one of the diff cover bolts.
4) OBD2 started in 1996 in most models. (A couple cars in 94)
Pats was a few years later.
Ford PCMs got easily tun-able after 2004
Not sure what to suggest, if you get new enough to be awesome, you have computer network stuff to contend with. (My Bronco is running a 2003 based control system and I had to build a harness with 3 of the modules to make it run and shift. (PCW, GEM, and HEC) not trying to discourage you, but I had over 150 wiring diagrams between 1979, 2001 and 2003 model years to get everything working)
Do lots of research before you start, there are a few places selling stand alone systems, (all the groundwork is done)
I wanted to build my own, but there are many options.
4) The 4.0 swap will be great when its done, but it is a mountain to climb.
Have a few crown and waters (or whatever your poison happens to be…coffee works too!) and ponder a while.
The 2.9 isn’t bad either. There is nothing that can’t be fixed.
With yours its time to put down the shovel and re start, we must have missed something. Online diag is very difficult as only one of us can see the results Of a test and often small bits get missed in the info transfer.
Just my 2 cents
Cheers
 
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grumpy old man

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My first day out of bed and I will be heading back soon. had another lung collapse and wound up having lung surgery to repair all the damage. You probably will not be hearing from me any time soon.
 
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grumpy old man

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Believe me if there were something I could do to stop all this I would do it in a heartbeat.

My first day out of bed was yesterday, got all the tubes and stitches out and went right back to bed. Got up this morning and decided to attempt to catch up with month end stuff. Hour and change and I am wiped out and back to bed.

Told the doc, never again. you ever want to see my lungs again bring a gun and **** me. You can look all you want at the autopsy.
 

johnnyreb

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My first day out of bed and I will be heading back soon. had another lung collapse and wound up having lung surgery to repair all the damage. You probably will not be hearing from me any time soon.
Sorry to hear that. Prayers to you Grump. We all wish you a speedy full recovery. and be thinking about you.
 
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grumpy old man

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Last couple of days I have felt marginally better. Having my last post-op next Monday. Think I will drive the B2 as the Dr's office is on the other side of the smog station. Think there might be a small chance of the blasted thing passing. It still sets the code 41 but it is a momentary thing. If you turn the key off and back on the light goes out. Apparently something is getting slightly above or below limit and triggering the 41. It seems to happen coming down from a 70-75 MPH run and playing with the throttle to settle into the slower traffic. I don't know what is coming out of the tailpipe as I have not managed to wrap my fingers around a 4 gas analyzer so need to put it on the rollers.

Figured I will give it a go and see what happens. If it passes and I can complete the registration I am done with it for this year. Will pick up on the 4.0 when I am actually back to 100%. Right now I am not allowed to pick up anything over 10lb, which probably means I can't even go to the grocery and get a gallon of milk. Such fun!
 

johnnyreb

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Well take it easy Grumpy--we know its hard after a person has been used to doing things. My sister keeps getting on to me too. Get well and have a speedy recovery.
 

wyo58

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Last couple of days I have felt marginally better. Having my last post-op next Monday. Think I will drive the B2 as the Dr's office is on the other side of the smog station. Think there might be a small chance of the blasted thing passing. It still sets the code 41 but it is a momentary thing. If you turn the key off and back on the light goes out. Apparently something is getting slightly above or below limit and triggering the 41. It seems to happen coming down from a 70-75 MPH run and playing with the throttle to settle into the slower traffic. I don't know what is coming out of the tailpipe as I have not managed to wrap my fingers around a 4 gas analyzer so need to put it on the rollers.

Figured I will give it a go and see what happens. If it passes and I can complete the registration I am done with it for this year. Will pick up on the 4.0 when I am actually back to 100%. Right now I am not allowed to pick up anything over 10lb, which probably means I can't even go to the grocery and get a gallon of milk. Such fun!
Take care of you first grumpy the other stuff can wait! Get well soon!
 

Tiha

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Dang, Take care of yourself. Collapsed lung is pretty scary stuff.

Had a thought though, I wonder what would happen if you added like 5 gallons of straight ethanol to the tank.
Granted it would be hard for rubber parts, but I wonder if that would bias the O2 enough to get it to pass.
 
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grumpy old man

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Not as scary as the surgery to repair damage.

On that note. Saw the Dr. yesterday, She told me that I could cancel my appointment with Pierce Brothers, I am probably going to make it.

On the way back stopped at the smog shop and I am back to where I was at after the very first test. Every thing else is in spec but the NOX are about 70 points too high. Back in December before all the covid and lung problems I started going backwards on the Bronco. Put the first replacement O2 sensor back in, can't find the original in my absolutely impeccable garage and the original MAP sensor. Plugged in the break out box and started checking everything that would offer data, KOEO and KOER. TPS was out slightly so I replaced that. Got everything within spec shown in the emissions manual and was going to go back for another test when I was offered the medical vacation.

I am going to back timing out of it until it starts to feel sluggish then put a few degrees back in so as not to ***** up everything else, and see what that does for the NOX. I have figured out that the heads have been off of this thing and got to wondering if possibly the wrong heads were put back on and changed the compression ratio? Quite often when starting, the starter has a slight problem pushing the first cylinder over the top but then is fine. A higher compression ratio will certainly affect NOX. It does not have EGR or I would be looking there. Will start with timing as it is easiest.

Now the code 41. On the surface streets it will set the code within a couple of miles. On the freeway it seems to be fine until you change the throttle setting. May go for 15+ miles cruising until you move the throttle. Coming back home I was cruising along in light traffic crested a slight grade and backed out of the throttle, CEL instantly set. To me that says vacuum but what? Not going to worry about that right now as it will not affect a smog test but it is the first time I have observed what seems to be a direct connection between throttle and light.

Been thinking about the 4.0. This thing runs so great that I don't see the point in adding another 70 cubic inches. 70 HP at best ain't going to make or break this thing and she will never notice the difference. Buttttt, is there a way to change to an OBD2 system with the current engine? I do after all live in that foreign country known as Commifornia. They do get real weird about stuff like that.

Just sitting here thinking weird thoughts since I can't do anything else.
 

johnnyreb

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Well we hope everything goes good for you Grumpy. Prayers for you bud and good luck getting the bronco figured out too.
 

L\Bronco

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Not as scary as the surgery to repair damage.

On that note. Saw the Dr. yesterday, She told me that I could cancel my appointment with Pierce Brothers, I am probably going to make it.

On the way back stopped at the smog shop and I am back to where I was at after the very first test. Every thing else is in spec but the NOX are about 70 points too high. Back in December before all the covid and lung problems I started going backwards on the Bronco. Put the first replacement O2 sensor back in, can't find the original in my absolutely impeccable garage and the original MAP sensor. Plugged in the break out box and started checking everything that would offer data, KOEO and KOER. TPS was out slightly so I replaced that. Got everything within spec shown in the emissions manual and was going to go back for another test when I was offered the medical vacation.

I am going to back timing out of it until it starts to feel sluggish then put a few degrees back in so as not to ***** up everything else, and see what that does for the NOX. I have figured out that the heads have been off of this thing and got to wondering if possibly the wrong heads were put back on and changed the compression ratio? Quite often when starting, the starter has a slight problem pushing the first cylinder over the top but then is fine. A higher compression ratio will certainly affect NOX. It does not have EGR or I would be looking there. Will start with timing as it is easiest.

Now the code 41. On the surface streets it will set the code within a couple of miles. On the freeway it seems to be fine until you change the throttle setting. May go for 15+ miles cruising until you move the throttle. Coming back home I was cruising along in light traffic crested a slight grade and backed out of the throttle, CEL instantly set. To me that says vacuum but what? Not going to worry about that right now as it will not affect a smog test but it is the first time I have observed what seems to be a direct connection between throttle and light.

Been thinking about the 4.0. This thing runs so great that I don't see the point in adding another 70 cubic inches. 70 HP at best ain't going to make or break this thing and she will never notice the difference. Buttttt, is there a way to change to an OBD2 system with the current engine? I do after all live in that foreign country known as Commifornia. They do get real weird about stuff like that.

Just sitting here thinking weird thoughts since I can't do anything else.
Hey Grumpy, glad to hear you are on the mend. Sounds crazy scary though.
A thing to consider is a lean condition will definitely give high NOx readings as well. ( your compression ratio theory is sound too, any static compression numbers?)
Changing to OBD2 is a mountain to climb. The easiest way would be to swap eng, trans, cluster, and all the computers from an OBD2 explorer, then contend with all the peripheral stuff that comes up.
Can you get O2 sensor voltages while cruising?
Plus an air charge temp sensor voltage along with the outside temp.
Your 41 has me vexed.
I think fixing the 2.9 is the answer. You have something going on for sure and its likely simple. (Most of the ones that have bitten me have been in the end.)
When you are up to it, I would treat it like you haven't worked on it before. Reset and restart. (Just keep all of the old data in the back of your mind) no more parts, just test a few things.
My racing season has started up again, (Bakersfield last weekend and Pomona in 3 weeks) so I will be intermittently away from the zone for a while, but I think we can get to the bottom of it if we can be very deliberate and focused with our testing.
Let me know and take care.
Cheers
 

johnnyreb

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Hey Grumpy, glad to hear you are on the mend. Sounds crazy scary though.
A thing to consider is a lean condition will definitely give high NOx readings as well. ( your compression ratio theory is sound too, any static compression numbers?)
Changing to OBD2 is a mountain to climb. The easiest way would be to swap eng, trans, cluster, and all the computers from an OBD2 explorer, then contend with all the peripheral stuff that comes up.
Can you get O2 sensor voltages while cruising?
Plus an air charge temp sensor voltage along with the outside temp.
Your 41 has me vexed.
I think fixing the 2.9 is the answer. You have something going on for sure and its likely simple. (Most of the ones that have bitten me have been in the end.)
When you are up to it, I would treat it like you haven't worked on it before. Reset and restart. (Just keep all of the old data in the back of your mind) no more parts, just test a few things.
My racing season has started up again, (Bakersfield last weekend and Pomona in 3 weeks) so I will be intermittently away from the zone for a while, but I think we can get to the bottom of it if we can be very deliberate and focused with our testing.
Let me know and take care.
Cheers
Good luck with the racing L/Bronco--you all take care--good luck and be careful. I hope your health is going good too. My results was good last week.
 

johnnyreb

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Dang, Take care of yourself. Collapsed lung is pretty scary stuff.

Had a thought though, I wonder what would happen if you added like 5 gallons of straight ethanol to the tank.
Granted it would be hard for rubber parts, but I wonder if that would bias the O2 enough to get it to pass.
well it would probably blow the mufflers off of it --if you got on it. I used to put a bottle in every fill up along time ago. My brother put 2 in his ss 396 and as he got on it---blew both mufflers off of it. Gotta watch and be fast changing gears and watch the tach. It does make a difference-plus we had real gas back then.
 
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grumpy old man

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Scary? You should see it from my side. As I told the Dr. on my last visit, the only way you will ever see my lungs again is if I am on an autopsy table.

Well It will be at least three weeks. The restrictions I have on me I can't even set the timing. First thing on the to do list, and if necessary 2nd,3rd,etc. get it smogged. Need to finish the registration. DMV is sending me nasty letters.

Once DMV is in the rear view mirror I can attack the 41at my leisure. I can get all the data available just need to find a driver. Break out box is lap sized, just need to move pins around and connect the DVOM.

What is in Pomona? I may not be able to do anything or walk very far but I can drive and watch once there.
 

johnnyreb

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Scary? You should see it from my side. As I told the Dr. on my last visit, the only way you will ever see my lungs again is if I am on an autopsy table.

Well It will be at least three weeks. The restrictions I have on me I can't even set the timing. First thing on the to do list, and if necessary 2nd,3rd,etc. get it smogged. Need to finish the registration. DMV is sending me nasty letters.

Once DMV is in the rear view mirror I can attack the 41at my leisure. I can get all the data available just need to find a driver. Break out box is lap sized, just need to move pins around and connect the DVOM.

What is in Pomona? I may not be able to do anything or walk very far but I can drive and watch once there.
L/Bronco goes racing down their.
 

L\Bronco

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Scary? You should see it from my side. As I told the Dr. on my last visit, the only way you will ever see my lungs again is if I am on an autopsy table.

Well It will be at least three weeks. The restrictions I have on me I can't even set the timing. First thing on the to do list, and if necessary 2nd,3rd,etc. get it smogged. Need to finish the registration. DMV is sending me nasty letters.

Once DMV is in the rear view mirror I can attack the 41at my leisure. I can get all the data available just need to find a driver. Break out box is lap sized, just need to move pins around and connect the DVOM.

What is in Pomona? I may not be able to do anything or walk very far but I can drive and watch once there.
Man, make sure you take it as easy as your upbringing will allow. (The "old guys" will know what I mean here, :sneaky: :cool:

The NHRA winternationals are a drag racing event at the Track there (google NHRA winternationals and you will get a bunch of info.) I am the car chief (volunteer), on a LEGENDS nitro-funnycar and its one of the events we do down there. Its pretty cool, and it keeps me busy.
IMG_5548.JPG
This is in Pomona last year.
Let me know when you are able to get to the Bronco 2 and we will see if we can getthrough it.
No rush.
Cheers
 

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