'68 Bronco John Deere theme

[Dignlif]

Ok first off, this isn't mine but I wish it was. It belongs to the guy I asked about putting a 4BT into the '68 Mustang project. I've decided on a different course for that car after discussions with him but that will be a different thread.

This is his '68 Bronco but the John Deere theme is far more than skin deep beauty or coolness. Beyond the paint, this thing is actually powered by a 4.5L JD tractor engine.

The wheel base was changed by stretching it 1 foot forward and 1 foot rearward. He worked out and built the suspension parts himself. The fender wells were also moved to center over the wheels.

The interior has comfortable aftermarket seats and a full overhead cage along with the JD gauges and JD ignition key/ switch.

And now for what probably interests you BS'ers more than anything - drivetrain. It has a 4.5L JD tractor engine with a compound turbo setup designed by Bell Turbo. The two wastegates are set to 15 and 32 but he's never gotten enough rpm to hit the second one. The highest he's seen is about 26 on the bigger turbo, not that he needs any more.

On the initial tune at the dyno, the setup gave him 297 hp with 632 lb/ft torque and all that umph under 4200 rpm. He believes that with the new tuning, he's gotten it to run a bit better.

He had a custom adapter plate cut on a CNC and backing the engine is an NV4500 trans putting the power to the Atlas transfer case and then to the diffs with air lockers.

Here's yet another cool deal about it... how does 44-46 mpg sound? not good enough? Well that was when he went hunting with all his stuff loaded and pulling a little trailer with further supplies. Lets try his trip to Reno where it only sipped 3.5 gallons for the 187 mile trip - the math says that's 53 mpg folks.

Ok you say 'it must be a lightweight'...uh no. That's a tractor engine remember. Try 3200 lb's on just the front tires with another 2800 or so on the rear. He used a 4 scale setup to find this out so it's pretty accurate.

And...he believes(and plans to test it) he can get it to pass the SMOG sniffer test even though the Bronco's age negates the need for it.

It's just an all around way cool rig that he built and drives wherever he wants. Hope you enjoy.

Now the pix.

[milner351]

FANTASTIC! I totally love this thing - and I don't like green.

I find the mpg claims a bit pie in the sky - are his distances measured with a gps? I'm wondering if the speedometer / odometer relationship is correct if he's using the ODO.

With the weight of 6000lb, barn door esque aero, and aggressive tread wide tires, even if he's dead on the BSFC fuel curve - that's ALOT of rolling resistance, parasitic loss and aero drag.

" 3200 lb's on just the front tires with another 2800 or so on the rear. He used a 4 scale setup to find this out so it's pretty accurate. "

[JOES66FURY]

Funky!

Odd choice for a drive train but who the hell can argue with 600+ftlbs all under 4200? Holy stump pulling awesomeness Batman!

I have seen full size Rams with a Cummins knock down 22 or better, also small diesels have been well known to knock down Prius killing MPG, no reason I can find to argue his claims...especially when the whole thing probably weighs two pounds more than diddly squat...

[Dignlif]

FANTASTIC! I totally love this thing - and I don't like green.

I find the mpg claims a bit pie in the sky - are his distances measured with a gps? I'm wondering if the speedometer / odometer relationship is correct if he's using the ODO.

With the weight of 6000lb, barn door esque aero, and aggressive tread wide tires, even if he's dead on the BSFC fuel curve - that's ALOT of rolling resistance, parasitic loss and aero drag.

" 3200 lb's on just the front tires with another 2800 or so on the rear. He used a 4 scale setup to find this out so it's pretty accurate. "

hmm I don't know the specifics or about using a gps John but google maps shows Center of Stockton to center of Reno to be 180ish miles so that kinda takes the speedo correction out of it. My guess is he topped out fuel in Stockton and then again in Reno to try and get an idea of usage. I think what he's most proud of is that it runs so clean for being an ag engine. That's why he's going to get it tested on the sniffer, to prove it can be done.

I understand your standpoint from a weight/ resistance aspect so can ask the next time I'm up there. Even going down the road at 2000 rpm uses fuel. I know he's not a guy who needs to make unsubstantiated claims to feed his ego though. He's really a down to earth guy who owns a shop where he works on farm equipment/ trucks by day and likes to build cool stuff for himself.

[Deaf Bob]

I like the idea!
I'd use a FJ40... Or a FJ55. Hell even a FJ45

[SuperBuickGuy]

gear ratio?

[Beagle]

I think you guys are missing the big question - at what MPH, and it still doesn't matter cuz the thing (other than the green - haha... ) is just cool as hell!!

no head gasket problems at 300 hp? That's what, 3 times it's original HP rating? Does he have install pics, process, stuff he ran into details? I love this thing. I have been looking recently a little harder than normal for a 4cyl diesel for a hyper-miler project. I almost think I understand a little about diesels now, but still question question questions!!

875 pounds worth of Four cylinder? YIKES!!

[Dignlif]

gear ratio?

Sorry I'll have to go back and ask about that again too as I didn't have it in my notes.

He first built it a couple years ago with a 302/ C4 combo but then decided to go all in with the the JD theme. I don't have any build pix along the way but I'll see if he has any that I can share.

I'm with Beagle, even if I misquoted the mileage (I'll double check), it's just a damn cool rig that has a very different engine in it. Did you notice the hand built diamond plate oil pan? He started it up for me and it came to life with no hesitation and sounded great w/o sounding like a rattling tractor engine.

I'll try to get back out to his shop soon to answer your questions better.

[milner351]

this is purely fantastic - Rich I in no way intend to dis-credit this guy - I'm just wanting to know more! The build is amazing.

Ag engines which I know little about, are generally designed to be very efficient in the most used RPM range - like a generator engine running at a constant speed to produce electricity at 60hz.....

so - if he's matched his gearing and tire size to be close to the "ideal" point on the engine's fuel curve - he is going to get great mileage.

The one thing I agree with banks about is "performance without the smoke" black smoke is for spectators - it's a waste of fuel - I understand the "rich is safe" argument - but stupid rich is stupid, period.

This vehicle is simply an overflowing bucket of win - even if it is green. I've had visions of things like this for years - this guy went and did it, I love it.

It's also proof that there's more to a diesel conversion than a 4bt / 6bt - not that there's anything wrong with those. but I dare say a running turbo diesel tractor engine that ISNT one of those two is cheaper because of it.

[Dignlif]

I know you're not hacking on it John. It certainly is a big number stated for mpg so like I said I'll get more information. Short of actually riding along on a trip I guess there's no absolute way to substantiate anything he says. Another friend commented on the layout of the suspension potentially being a bit stiff so I'm not saying it's perfection. I just really like what he did with it and how he put it together so wanted to share. Lots of custom touches to it and very different. He made something work that to my knowledge hasn't been done for something on the street (ag engine). It's a big enough deal that JD is scheduled to check it out at his shop.

He also has a really nice 68 Shelby clone with a 428 CJ and another Bronco that is show quality with tons of detail. He doesn't drive either of those much but spends alot of time beating on this thing and loves it.