engine swap options for a 96 XLT

[Lee]

What are my options for replacing the 2.3L Lima in my 96 Ranger XLT

Better gas mileage is what I'm after.

My old 2003 ranger got 29 mpg but this 96 barely gets 24

Are my options only between the 2.3 Lima & the 2.5???

Thanks Lee

 

[RonD]

Yes, pretty much, Lima engines have unique bell housing pattern.

If you want to change the transmission as well then you could "try" a Duratec 2.3l swap never seen it done but I am sure someone has.
Duratec is newer design and simply a more efficient engine, just like the Lima was more efficient than a 60's 4cyl.
This is why the '03 Duratec 2.3l got better MPG, but it also may have had lower axle gearing.

Look on the drivers door sticker for the Axle code, then go here: http://www.therangerstation.com/tech_library/axle_codes.shtml
See what your current axle ratio is.

Ranger's popular axle ratio was 3.73, which is OK for towing and OK for MPG but not Great at either.
3.08 is great for MPG, highway speeds, but sucks for towing
4.10 is great for towing but sucks for MPG, highway speed.

Is your truck a 2WD or 4x4?

 

[Lee]

Ron thanks for the quick reply.

I looked up the axle code from the door sticker.

Its an 86 which translates into a open 7 1/2" with 3:73 gears

My truck is a 2WD

I'll start looking in the junk yards for a 3:08 axle & do a axle swap.


Back to the original question, would I gain any mpg swapping to a 2.5L or would it be purely a HP gain?

Thanks Lee

 

[RonD]

Switch from 3.73 to 3.08 would drop the RPMs by 400 at 65MPH, and that's about a 20% drop, approx. 2,250 down to 1,850 assuming 27" tires in OD(5th gear)

2.3l engine sucks in 2.3liters of air for each 2 RPMs, 4 stroke engines needs 2 full revolutions of the crank shaft for each complete cycle of all cylinders firing.
Fuel use for gasoline engines is based on 14:1 air:fuel ratio
The more air that is used the more fuel is used.
And the more fuel that is used the more power the engine generates.
Use more air get more power, that's why turbos add power, and why a 5.0l has more power than a 2.3l or 4.0l, more air, lol.

2.5l engine would use........................2.5liters of air per 2 RPMs
So would use slightly more fuel and generate slightly more power.
2.5l has a longer stroke of the pistons which translates into better torque more than horse power
1996 2.3l
112HP
135ft/lb torque

1998 2.5l
117HP
149ft/lb torque

While the extra torque would be nice, especially with 3.08 gearing, your MPG wouldn't be as good with 2.5l

 

[Lee]

WOW you really know your ranger engines.

Thanks for pointing me in the right direction Ron.

Any kind of rough idea what mpg I could expect if I were to do the axle swap??

Thanks Lee

 

[RonD]

No, still learning, hopefully to the day I die

Hard to "guesstimate" MPG gain.
The more highway driving the better the MPG improvement over the 3.73
But your "get up and go" with the 3.73 won't be there, truck won't feel as "peppy" as before, that's the trade off(the no Free Lunch part, lol), which may get you to put your foot in it a bit more, which, of course, brings down the MPG.
Acceleration won't be awful, 3.08 was an option for the 4cyl Rangers, you just may notice the difference since you have driven the 3.73 for awhile.

I would also look at an electric radiator fan and remove the belt driven fan, this is better for MPG and frees up some HP.
Belt driven fan is always spinning, it's clutch helps reduce the HP drag when engine is cold but it is always spinning so always a drag on power.
E-fan does use alternator power, but only when it is on, which is not that often on the Lima engines, they just don't generate much heat.
Good read here on E-fan swap: http://www.therangerstation.com/Magazine/Summer2003/ElectricFanInstall.htm

 

[bobbywalter]

Switch from 3.73 to 3.08 would drop the RPMs by 400 at 65MPH, and that's about a 20% drop, approx. 2,250 down to 1,850 assuming 27" tires in OD(5th gear)

2.3l engine sucks in 2.3liters of air for each 2 RPMs, 4 stroke engines needs 2 full revolutions of the crank shaft for each complete cycle of all cylinders firing.
Fuel use for gasoline engines is based on 14:1 air:fuel ratio
The more air that is used the more fuel is used.
And the more fuel that is used the more power the engine generates.
Use more air get more power, that's why turbos add power, and why a 5.0l has more power than a 2.3l or 4.0l, more air, lol.

2.5l engine would use........................2.5liters of air per 2 RPMs
So would use slightly more fuel and generate slightly more power.
2.5l has a longer stroke of the pistons which translates into better torque more than horse power
1996 2.3l
112HP
135ft/lb torque

1998 2.5l
117HP
149ft/lb torque

While the extra torque would be nice, especially with 3.08 gearing, your MPG wouldn't be as good with 2.5l

these are great metrics, text book basics for the most part. no arguements there.


but there is much more in the comparatives then you would think.

the actual condition of this powertrain in its entirety vs baseline oem is a key starting point.


going to 308 gearing will likely result in worse economy the way you sit right now.. unless you slam the truck and put tiny tires on it. you have to match the tire size to the 308 gears.....this can be the mpg champ with less rolling stock to move in city traffic. and do well on the highway. in theory anyway.


theory



all things being equal, the 2.5 will almost always get better mpg. its better. a 3.7 v6 will beat the 2.3 mpg in this application stock to stock and all things being equal. and it is 1.4 liters larger.

you can run a custom ring and piston package with the 2.3 you have now with reduced throw weight and balancing and cleaned up h.c.i. combination and mild tune and produce 20 to 25 percent more power all around and get close to matching fuel economy.


this would exceed the 2.5 power a bit and get close to economy......and cost 2-3 grand. but theres better combinations, proven combinations that will get to 180 plus hp and well over 200 ft pounds. they will get best economy with 410 gears and 235 tires at 65 mph. but that would probably be 18-19mpg...and cost much more.


on the other side of that 6.5 liters in a 6000 plus pound truck can pull 25 mpg on the hiway. sure the fuel is responsible for 30 percent of that, but 6.5 liters is much more then double the air capacity of a 2.3......


so theory is just for basic descriptors..... determining the actual condition of your engine and spending the time with a dynotuner for fine tuning the engine to fit your driving needs are things you can do to work with what you have. 30 mpg with a 2.3 in a ranger though is not the easiest thing to do.


but it does get done.

whether or not a e fan will help enough to notice depends on your actual drive cycle conditions.....but it is a 100 percent benefit item as far as variables are concerned. some people just cant understand that though.


if you have the skills and its not a high cost swapping a 2.5 powertrain could easily be the easy button for 30 mpg.

 

[Lee]

Looks like I asked the right folks.

I've been thinking about swapping to the 2.5 mainly because this 2.3 has about had it, plus the added HP never hurts anything.

Swapping to the Duratec 2.3L would be nice but I could probably buy a used 2000+ Ranger for less than all the parts needed for the conversion

I was curious what mpg you could get out of a 2.5L w/ 3:73 gears

Thanks Lee

 

[Mikel89us]

Bobbywalter is spit on. The displacement isn't a direct reflection of mpg. The reason a 3.7l v6 can be more fuel efficient, aside from the fact that its newer, and more efficient, is that a v6 will make mor torque at a lower rpm than a 4cyl. Mpg is all about usable torque. You can have a v8 that at 20% load makes 50ftlbs of torque at 1500 rpm, and it will only put out roughly 15-20hp. A 4 cyl to make the same hp, requires more throttle(load) or speed to put out the same hp, while probably making less torque. This isn't exact science, but the theory is sound enough.

 

[Mikel89us]

I will also say, I went from stock tires and a 3.73 in my mustang, to smaller tires and a 3.27, and I saw a drop in mpg.