Before I get started, let me say at the outset that this project is for down the road a piece once I get back on my feet, not something that I have the parts for and am starting the day after tomorrow.

My current driver is a Suzuki Sidekick Sport with the 1.8L I4, 5sp, and 4x4. I get right around 20 MPG out of it if I behave myself. It is cramped and puts me too close to the road for my comfort, though, and I am looking at replacing it. I have a notion that a Bronco will serve quite nicely as a replacement.

What I'm thinking is a '92 through '96 at stock height with a 5-speed, manual transfer case, 235/75R15 Wild Country XTX tires, and a 4.9L six would do everything I need it to do. (And yes, I am aware that the Bronco/4.9L combo was discontinued for 1993.)

If you were working on this project, would you use the M5R2 or the S5-42/47? Or would you be more interested in a four-speed behind a Ranger 10? I figure the Mazda would give more even splits between gears, the ZF is stronger and has the crawl ratio, and the 4-speed/Ranger 10 setup would give me six gears along with two crawl ratios at the expense of relocating the gear boxes seven inches to the rear.

What gears would you run? I'm thinking something between 3.08 and 3.55 would do what I want. 3.08 would give me about 1800 RPM at 60 MPH, if I remember my calculations correctly.

Stock cam or something aftermarket? and which aftermarket cam?

Stock exhaust manifolds, or headers? I expect that a 2.25" exhaust system from the cat back would be the preferred option there.

Keep in mind I'm not after some 20,000 RPM screamer; I want something that will run forever, get 20 MPG (or better, if possible), and give my six foot plus height some room behind the steering wheel. I want quiet, reliable, and thrifty.

 

If you are going for mileage only, use the M5R2 trans, 3.08 gear, and convert it to 2wd. Leave the motor stock.

 

Ah, but here in Iowa I have snow to contend with too -- hence the Wild Country XTX tires with the Severe Snow rating.

Would you leave it as a speed density engine, or would you convert it to MAF? (The '95 California F150 looks like a promising source for the MAF conversion, with only one additional HO2S. The '96 adds two.)

 

I don't think MAF is going to help the MPG any.

 

If I was you, I would not use the 300. I would step up to a 302
The truck is light enough that the 302 will get good fuel milage and actually have power.

As for gearing I would be looking at 3.55 or 3.73….. 3.08 are too high for anything with that small of an engine

You may ask why the 302?

I have a 96 bronco with a 302 5speed(factory) w 6" of lift, 35" tires and 4.56 gears. I REGULARLY get 15mpg not driving like an idiot. I could only imagine what a stock height, stock tired bronco would do(makes me want to get a stock one for a commuter)

 

X2 on the 5.0L/302 build instead of using the 300 I6. Also agree with the gearing suggestion.

 

x3 on the 302 and 3.55+ gears. I would actually consider stepping up to 4.10's.

 

I don't have a problem recommending the 302, heck, I prefer it over the 300 myself, but telling the guy to put in 3.55s or 4.10s for MPG is wrong.

 

4.10s is pushing it, but 3.55 I think is good medium that the truck will have decent power yet not scream down the highway

 

If I can get out of my own way and keep up with traffic I'll be happy. I'm too old to be sprinting from stoplight to stoplight.

I'm not opposed to the idea of installing a computer-compatible "RV cam" along with the stock intake and possibly headers to reach my goals. (That's one reason I was considering a MAF conversion.) Does anybody have recommendations for a cam?

 

Last time I figured my mileage up, I was getting roughly 16 MPG with 6 inch lift, 35's, and 4.10's. I've got a stock Explorer motor in mine with stock Bronco intake but my cam is the same as the 351 truck roller cam (the Explorers got truck cams). I'm pretty sure my stock Bronco cam was non HO firing order. The HO firing order cam should help build more torque and better MPG.

 

Get a 5.0L from an Explorer, it has an excellent roller cam, GT40/GT40P heads and a decent intake. You could run a SD computer but I would lean towards a MAF just so you have better flexibility to do a custom tune to maximize your goals. The swap to MAF may not pay for itself in a short amount of time but it is something I would consider.