Power Upgrades 2.9l

[AllanD]

Unbolted my 2.9 and bolted in a 4.0.

Best thing I ever did to my truck.

The 2.9 was OK until I've now had the 4.0.

Now I view the 2.9 very similar to how I view the A4LD. They both look great in the rearview mirror when leaving the dump.

That pretty much sums up my feelings about the 2.9

I've put a bit over 30k miles on the truck since I swapped in the 4.0
The 4.0 is quite frankly everything everyone wants the 2.9 to be (yet something it never can be)

And comparing the 4.0 fo a 302 with a carb isn't fair... to the 5.0.

Because quite simply the 4.0 makes torque down low where you
really want it.

As for the trans? this depends greatly on which trans the 2.9 had originally...

AD

 

[Rick W]

A question for the motor masters…

Let’s say a guy had an 87 Ranger, 2.9, five speed, four-wheel-drive with a little bit of lift. When he got it, the engine was blown, but before he even bought it, he knew where there was a 2.9 with improved heads, rebuilt with 40,000 miles on it. So he bought the truck and bought the engine and did some other work. It absolutely runs perfectly, but the engine is lacking a little bit of power, climbing hills and such. He doesn’t use it in the four-wheel mode much, rarely goes off road except a construction site or such

And, let’s say he might want to modify the truck, and add a bigger trailer, just for fun, and he’s looking for a way to get a little bit more out of the 2.9. To be specific, he’s looking for more torque off the line and hill-climbing ability with a load, not more speed, as long as it will still go 65 miles an hour up a interstate hill, even if he has to downshift

And let’s say he’s got the 7.5 rear, with 345 gears.

Let’s say the guy is real cheap. He’s capable, he’s got money, he just doesn’t want to spend it. What can he do to the engine to give it a little more power, mostly torque, that’s just a bolt on, inexpensive?

Will bolt in taller gears on the rear end get him more torque off the line and on a hill? What’s involved in changing the gears, and remember the gears in the front would also have to be changed.

Did I mention the guy is creative, but he’s really really cheap?

I looked around on the site and I looked around on the web, and I found this thread, but everybody in this thread is saying trash the 2.9 and swap in a bigger engine. To this guy that’s not a realistic option, so what can be done to the 2.9 or the final gears?

This thread is almost 20 years old, so I was wondering if there was some more recent knowledge on how to improve the torque/pulling power of the 2.9, and the 345 finals.

Asking for a friend….

 

[Rick W]

Fallback option. Will a 4.0 OHV just bolt in if I take out the 2.9? Very specifically, checklist, what else would I have to change out?

 

[lil_Blue_Ford]

@Rick W

So, my opinion, 3.45 gears are good highway gears in flat country and not much good for anything else.

My 88 Bronco II and the 89 B2 that I sold in college had the 2.9 with 3.73 gears on stock to 30” tires. They were sluggish but tolerable. My 92 Ranger and my blue 00 Ranger have 3.73 gears and 30” tires with a 4.0 and a 3.0 respectively. They both did reasonably well, which makes me inclined to say that the 3.73 gears are a good all-around for a stock-ish RBV for the average user. If you want a little more go and are going to haul, at a 30-31” tire size, 4.10 is where it’s at.

A throttle body off an EGR equipped 2.9 is significantly larger, I did that on my Choptop before I did the 4.0 swap. There’s also some other stuff that can be done. When I get some projects cleared out I’m intending to do some tweaks to a 2.9 in my 88 and see how it goes.

4.0 OHV basically bolts in. Fuel system has the wrong ends so you have to adapt. Transmission may or may not survive long term. The FM-146 in my Choptop is living a charmed existence. It will likely become M5OD when it gives up. The biggest problem with a 4.0 in the first gen trucks is the wiring. Everything needs spliced. If I’m going to go through that, there’s other engine options to consider…

 

[alwaysFlOoReD]

I would look for a 4x4 truck, or axles already out, with the right gearing (4.10) and swap axles. IMO that's cheapest and easiest.

 

[Rick W]

@Rick W

So, my opinion, 3.45 gears are good highway gears in flat country and not much good for anything else.

My 88 Bronco II and the 89 B2 that I sold in college had the 2.9 with 3.73 gears on stock to 30” tires. They were sluggish but tolerable. My 92 Ranger and my blue 00 Ranger have 3.73 gears and 30” tires with a 4.0 and a 3.0 respectively. They both did reasonably well, which makes me inclined to say that the 3.73 gears are a good all-around for a stock-ish RBV for the average user. If you want a little more go and are going to haul, at a 30-31” tire size, 4.10 is where it’s at.

A throttle body off an EGR equipped 2.9 is significantly larger, I did that on my Choptop before I did the 4.0 swap. There’s also some other stuff that can be done. When I get some projects cleared out I’m intending to do some tweaks to a 2.9 in my 88 and see how it goes.

4.0 OHV basically bolts in. Fuel system has the wrong ends so you have to adapt. Transmission may or may not survive long term. The FM-146 in my Choptop is living a charmed existence. It will likely become M5OD when it gives up. The biggest problem with a 4.0 in the first gen trucks is the wiring. Everything needs spliced. If I’m going to go through that, there’s other engine options to consider…

thank you, thank you

Copy that, but remember I’m a dummy at this specing it out part. So the 2.9 will unbolt, and the 4.0 will bolt right in? Same housing, clutch, linkage, etc.?

Is the fuel injection all the same? Please explain a little better on swapping the fuel connections.

Ditto on the wiring. In my mind, it’s a six cylinder to a six cylinder, so everything should work, yes/no? I don’t have to change any parts? I only have to clip wires and connect wires? Is that like a connect the green wire to the green wire, or do you have to know the secret codes and secret drawings?

Also, what is the “ throttle body off an EGR?” My 87 2.9 is not an EGR? EGR = Extra Great for Rick? What does this EGR come on and look like?

As always, all input appreciated. I won’t worry about the axles and the gear ratio until I figure out what I may or may not do to the motor.

 

[sgtsandman]

A question for the motor masters…

Let’s say a guy had an 87 Ranger, 2.9, five speed, four-wheel-drive with a little bit of lift. When he got it, the engine was blown, but before he even bought it, he knew where there was a 2.9 with improved heads, rebuilt with 40,000 miles on it. So he bought the truck and bought the engine and did some other work. It absolutely runs perfectly, but the engine is lacking a little bit of power, climbing hills and such. He doesn’t use it in the four-wheel mode much, rarely goes off road except a construction site or such

And, let’s say he might want to modify the truck, and add a bigger trailer, just for fun, and he’s looking for a way to get a little bit more out of the 2.9. To be specific, he’s looking for more torque off the line and hill-climbing ability with a load, not more speed, as long as it will still go 65 miles an hour up a interstate hill, even if he has to downshift

And let’s say he’s got the 7.5 rear, with 345 gears.

Let’s say the guy is real cheap. He’s capable, he’s got money, he just doesn’t want to spend it. What can he do to the engine to give it a little more power, mostly torque, that’s just a bolt on, inexpensive?

Will bolt in taller gears on the rear end get him more torque off the line and on a hill? What’s involved in changing the gears, and remember the gears in the front would also have to be changed.

Did I mention the guy is creative, but he’s really really cheap?

I looked around on the site and I looked around on the web, and I found this thread, but everybody in this thread is saying trash the 2.9 and swap in a bigger engine. To this guy that’s not a realistic option, so what can be done to the 2.9 or the final gears?

This thread is almost 20 years old, so I was wondering if there was some more recent knowledge on how to improve the torque/pulling power of the 2.9, and the 345 finals.

Asking for a friend….

The easiest and cheapest way to regear a truck is to swap in the axles with the gears you want already in them.

Just keep in mind that the front axle has to match the rear if you are going to keep the 4X4 system.

Now comes the decision point. Do you want better fuel mileage on the highway or have better get up and go at lower speed?

My experience with the 1998 when I switched from 3.45:1 to 4.10:1, fuel mileage didn't change but response and power in general driving improved significantly. Bear in mind, this was with a pretty gutless 2.5 Lima and I live in an area with a lot of hills and valleys. The 2.9 is going to have more horsepower and torque.

3.73:1 will usually give you better fuel mileage than 4.10:1 and some better get up and go and power compared to 3.45:1. If the truck seems to be struggling some with it's current gearing, 3.73:1 maybe the answer, especially since you seem to mostly stay on road and make highway trips to various events.

If you were entertaining bigger tires, I might recommend differently and to go with 4.10:1. Also, 3.73:1 is a more common gearing and will be easier to find and might be cheaper to get than 4.10.

As far as regearing you existing axles, you might save on parts but will get nuked on labor. Setting up new gears in a Ford axle is a lot of installing, checking tooth engagement, and pulling back out to reset spacers. The only reason I'm entertaining it on the 2011, is because the gearing I want is not offered in 2010-2011 axles and the rear axle only being made for two years, not super available.

 

[sgtsandman]

thank you, thank you

Copy that, but remember I’m a dummy at this specing it out part. So the 2.9 will unbolt, and the 4.0 will bolt right in? Same housing, clutch, linkage, etc.?

Is the fuel injection all the same? Please explain a little better on swapping the fuel connections.

Ditto on the wiring. In my mind, it’s a six cylinder to a six cylinder, so everything should work, yes/no? I don’t have to change any parts? I only have to clip wires and connect wires? Is that like a connect the green wire to the green wire, or do you have to know the secret codes and secret drawings?

Also, what is the “ throttle body off an EGR?” My 87 2.9 is not an EGR? EGR = Extra Great for Rick? What does this EGR come on and look like?

As always, all input appreciated. I won’t worry about the axles and the gear ratio until I figure out what I may or may not do to the motor.

The physical bolt in is going to be identical. Figuring out the wiring and what connectors are the same or different is going to require wiring diagram manuals for both to compare. Some rewiring might be required as well. Having the engines side by side to compare is probably going to be super beneficial as well.

 

[Brain75]

A thing to keep in the back of your head:
The 2.8, 2.9 and 4.0 (OHV not the SOHC) are all the same block - the 4.0 is just a bored and stroked 2.9. So generically, basically, they are the same engine. That said, different intake design, move sensors around year to year, etc etc. Almost all the mechanicals (trans, headers/exhaust,etc) should just bolt up UNLESS there is a difference Ford did to accomodate some other change elsewhere (like a moved sensor).

I'm the voice of the opposition here, everyone is wanting 3.55, 3.73, 4.10 .... I have to go 75 mph on the interstate (I live out west in the "Rocky Mountain" area where you can get up to 75 and drive it for hours without being in thick as thieves traffic) and the 2.9L + 3.45's I have stock (on stock tires right now) are perfectly fine.. If I went to a bigger numberical gearset my highway MPG would tank.. It is already kinda poor MPG at high speed since the truck was really designed when speed limits were 55 everywhere, and Ford just didn't design it to go 75mph.
I say put a couple of tanks of fuel injector cleaner through it, maybe seafoam it, tune it up and love it... if you want a racecar, buy a racecar, if you want to do superduty jobs with a truck, buy a superduty... the Ranger is a fantastic small truck (pre 98 when it was still a small truck), I love it as a small truck and it does everything I could want a small truck to do.

 

[lil_Blue_Ford]

thank you, thank you

Copy that, but remember I’m a dummy at this specing it out part. So the 2.9 will unbolt, and the 4.0 will bolt right in? Same housing, clutch, linkage, etc.?

Is the fuel injection all the same? Please explain a little better on swapping the fuel connections.

Ditto on the wiring. In my mind, it’s a six cylinder to a six cylinder, so everything should work, yes/no? I don’t have to change any parts? I only have to clip wires and connect wires? Is that like a connect the green wire to the green wire, or do you have to know the secret codes and secret drawings?

Also, what is the “ throttle body off an EGR?” My 87 2.9 is not an EGR? EGR = Extra Great for Rick? What does this EGR come on and look like?

As always, all input appreciated. I won’t worry about the axles and the gear ratio until I figure out what I may or may not do to the motor.

As has been mentioned, the block itself is pretty much identical between the 2.9 and 4.0 OHV, so yes, bolting it up is simple. I swapped to the 4.0 clutch in the Choptop when I did the swap. That was just the clutch and the flywheel that changed. You do have to use the aluminum plate between the engine and trans for a 4.0 and the 4.0 starter but the clutch hydraulics stay the same.

It is a return style system and the same pressure for the 4.0 up to 98, but there were changes to the motor. The problem is where the quick connects for the fuel lines are in the engine bay, they don’t match so you have to either make adapters or new fuel lines. I cobbled together some janky adapters years ago but I’m not happy with them. When I can get some time to deal with it, I’m replacing all of the fuel lines with -6 AN braided PTFE line, which is a little overboard probably and not cheap, but I know that if I do that, it should last the rest of my life and then some, plus I know that it’s a repairable system.

The wiring… it does NOT plug in, not even a little bit. The “closest” you will get is an engine harness and computer from a 90-92 Ranger, but the plugs that you need to have match up on the drivers side of the engine bay neither have the same plug style nor the same colors. You cannot use the 2.9 harness or computer on the 4.0 either. You need an EVTM for both the donor and for your rig. Figure out what two wires need to mate, cut and splice. Every one of them. That’s why I didn’t complete my original idea of a 4.0 swap on my 88 back years ago, back then I had no access to EVTM stuff to figure it out and no help to trace things out. I ended up using all the bits I had collected for the swap in my 89 Choptop because the wiring is much closer to matching.

The first year or so of the 2.9 offering had an EGR on the engine. Then it was dropped from there until end of the 2.9 being offered. The EGR equipped 2.9 had a throttle body on the intake so big you could almost stuff a tennis ball in it. The throttle body got significantly smaller when they removed the EGR from the motor. If you can find the older TB in the junkyard, it’s a free bit of power/throttle response for a non-EGR truck.

 

[Rick W]

A thing to keep in the back of your head:
The 2.8, 2.9 and 4.0 (OHV not the SOHC) are all the same block - the 4.0 is just a bored and stroked 2.9. So generically, basically, they are the same engine. That said, different intake design, move sensors around year to year, etc etc. Almost all the mechanicals (trans, headers/exhaust,etc) should just bolt up UNLESS there is a difference Ford did to accomodate some other change elsewhere (like a moved sensor).

I'm the voice of the opposition here, everyone is wanting 3.55, 3.73, 4.10 .... I have to go 75 mph on the interstate (I live out west in the "Rocky Mountain" area where you can get up to 75 and drive it for hours without being in thick as thieves traffic) and the 2.9L + 3.45's I have stock (on stock tires right now) are perfectly fine.. If I went to a bigger numberical gearset my highway MPG would tank.. It is already kinda poor MPG at high speed since the truck was really designed when speed limits were 55 everywhere, and Ford just didn't design it to go 75mph.
I say put a couple of tanks of fuel injector cleaner through it, maybe seafoam it, tune it up and love it... if you want a racecar, buy a racecar, if you want to do superduty jobs with a truck, buy a superduty... the Ranger is a fantastic small truck (pre 98 when it was still a small truck), I love it as a small truck and it does everything I could want a small truck to do.

I appreciate everybody’s responses. A little bit more about what I’m thinking. I have access to a very good running four-wheel-drive short cab short bed, almost exactly like my 87. And what I’m considering is another mini semi type project like I did with my 97.

My 87 with the 2.9 is fantastic for just tooling around doing whatever, hauling small loads, or driving down the interstate at 75. Really a great all-around little utility truck.

What I’m thinking of doing, is a similar double axle (or maybe a triple axle this time), with an aluminum trailer that may be three axles, with a low deck set up so it becomes an easy car hauler. A mini “tri drive” heavy hauler toy thing.

Before everybody jumps, this has nothing to do with right or wrong or the best way to move a car or any kind of common sense. It’s another big toy and crazy vision.

I’m not looking for a hot rod at all. Gas mileage doesn’t matter as long as it doesn’t drop to 10 miles a gallon What I want to be able to do is get more “tug off the line“ torque power, but still be able to go down the road at 60 or 65 miles an hour, and be able to drive uphill, even if I have to drop a gear. One gear. I want the engine strong enough to go 60 or 65 or 70 in an ideal world down the interstate, but if I come up on a hill (or a jerk in front of me), I want the torque to be able to downshift and climb the hill without dropping to 30 miles an hour or something like that.

In an ideal world, I would do this with an extended cab like my 97, but I’ve got my hands on the short bed short cab right now, and it’s a 2.9 with the five speed. All that is for clarity on my “vision.” or maybe clarity on my “delusion.“. I love my 97 for what I did to it, and if I found one in decent shape with a 4.0/5 speed, it would absolutely be my first choice. But I don’t wanna spend any money.

Having said all of that, I had a completely different thought. I have 235/75/15s on both trucks now. The 97 4.0 works perfect perfectly for this kind of stuff. The 87 seems a little underpowered when I climb a long hill even empty. If I downshift, it’s fine. But if I’m pulling a load, I would prefer to downshift as little as possible.

I have a pile of wheels out next to the shed of miracles, and I have a bunch of 185/65/14 tires on bullet hole wheels. Bullet holes would be my preference for a project like this. If I simply swap those two wheels/tires, it goes from 699 revs to 860 a mile. Wouldn’t that accomplish the same thing as putting in taller gears?

I’m not sure if I’m a fan of the appearance of smaller wheels and tires, but so much behind the doors will be custom, it’s just a matter of making it look right.

so, forget the best way to get it done, what’s the cheapest way without actual chickens running in a wheel on the roof?

 

[SenorNoob]

Shorter tires is almost exactly the same as higher ratio gears. Gotta be careful of going too narrow on a regular pickup or it can get tippy. IDK how that would play into your project. Probably non-issue. Definitely the cheapest way to go.

Will the 2.9 ever have enough power to comfortably tow another vehicle? What about legal issues? I know you're far more well versed in that than I with your 97.

Good luck.

 

[alwaysFlOoReD]

There is a calculator on site that would give you the info to figure out how tire size changes gear ratio effect.

 

[Rick W]

Wheel-size.com. I used it every day when I was working on all these things a few years ago.

I wouldn’t use a tire as skinny as I illustrated, I just have a bunch of them laying around on Ranger rims, so it would be an easy way to check how the truck would perform.

edit, correction: I might use those little tires on the trailer, but not on the steering or drive to tires of the truck

 

[alwaysFlOoReD]

I don't know why you wouldn't? Its not like you're hauling a ton of mass. As a rule of thumb, the tire pressure being the same, both those tires have the same pounds per square inch transferring load to the ground.