F250 4bt conversion

[THedlund]

Hi all. Newbie to diesel as well as diesel conversions so I have a few questions about converting my old Ford to diesel and was hoping that some of you may have a little insight on some of the hurdles I may encounter. From the sounds of it the 3. 9L would be just about right, weight and power wise. I don’t really want to change the drive train mainly due to costs.

It seems the old bread trucks that came with the 4bt/T19 are the most reasonable way to go. With the whole truck I should have most the parts needed for the engine conversion. The transmission conversion will cost a bit because I want to change to the NV4500 to get the over drive option.



Truck Spec’s:

1984 F250 Extended Cab

Dana 44 front

Dana 60 rear

Borgwarner transfer case

460ci

C6 transmission

4. 56 gear ratio

35” tires

3” body lift

@ 70mph the engine spins about 3000 rpm

weight of truck = 6000lb



What I’d like:

Doable on a shoestring budget

Daily driven

Able to pull a 5,000# boat/trailer at highway speeds

Decent 4wd capabilities

Fixed in the bush with gum/duct tape/bailing wire

Top speed of about 85 mph



4bt vs 6bt:

Power (has to work with stock drive train and suspension) what kind of power output is capable the 4bt capable of? Or would it be better to go with a 5. 9L?

Mileage? Getting 9mpg on a good day right now. Plus I’d like to be able to run bio/fry oil/or whatever else I can get my hands on.

Engine weight?



Engine Install:

Will stock fuel tanks work (fuel line size)?

Alternator?

Power steering?

Air conditioning (mounting pump, stock condenser location going to work)?

Power brakes (vacuum or hyd)?

Fuel pump (will a second electric pump help)?

Front cross member (need to be adjusted to fit oil pan)?

Firewall (need to be adjusted to fit turbo or engine set back)?



Transmission Install (NV4500):

Where’s a good place to get one (used/new/rebuilt)?

Is length similar to stock C6?

Positioning in truck (stick)?

Hydraulic clutch hook up?

Assuming that a hydraulic clutch pedal from a similar year will fit?

What type of clutch to use?

Will stock flywheel be adequate (from donor truck)?

Adapters to engine block and transfer case?

Oil cooler?





Thanks

 

[JCrockett]

Check these guys out

http://www.fordcummins.com/



http://www.autoworldmt.com/



Both places can help you out a great deal. I would opt for the 5. 9L if I were you. You have the room and the power upgrades are simple and cost effective, especially if you get a 12 valve with the P7100 Pump. I love mine! Could not be happier, about 350HP and the crank and getting 20+ mpg empty. I have almost 1000 on the conversion and no problem yet.

The truck is so fun to drive now Oo.



I used the entire Dodge drivetrain from the 97 Donor I had. It worked great, very straight forward and simple.

 

[CCahill]

You'll be $ and hours ahead buying an older 12v... . really... .

 

[FordCummins]

Definitely use the 6bt if you plan to swap it into an F250.

 

[Rotty]

I bought on auction a bread truck with 4bt and T19 transmission recently. It is a F350 chassis SRW. You could use all of the parts for your conversion. I would not discount the 4bt for power. It moves this 7000lb bread truck quite well. It has a T19 with a 4. 00 first gear. The pump is easily tweakable and a good starting place. It will also net you some good fuel mileage. If you are much more power, then the 6bt. 4bt with the P7100 pump are extremely rare in the auction/resale market. Most bread trucks 99% are the rotary type cpl858 105 HP.

Their are several flavors of the engine with a gear drive hydraboost or gear driven vacumn pump or vbelt vacumn pump. I would inspect the truck and make your decision which version you want for your application before you buy.

Good luck... .

 

[THedlund]

Thanks for the info. I guess my biggest worry is that the 6bt is too heavy for the front suspension and axle. I like the mileage possibility with the 4bt, but I also like the power to smoke some unsuspecting chump off the line and if a 6bt can still get a good 20mpg that ain't bad. I thought about just getting an early 12v but I prefer the ford body style plus I have more time than money so I can slowly gather parts for the conversion over time. Is there length issues with the 6bt in the engine compartment? Thanks again guys for all the help.

 

[THedlund]

anyone know how much you can crank the 4bt up to in stock form and how easy is it? what kind of aftermarket support is there for this engine?

 

[Scot]

Space should not be an issue. See sig and gallery.

 

[FordCummins]

There is a fairly good aftermarket for the 4bt, depending on what parts you need, some of the performance stuff interchanges. As for injector pump mods, there will be no shortage of them. Shops like PDR would be able to help with that.

 

[KellyClark]

I hope I don't start a discussion over the virtues of the 12v on your thread :-{} , but you should consider a newer HPCR motor. The 12v are powerful and simple, but the last one was built over a decade ago. That leaves you with paying for a rebuild, or swapping in a high mileage engine that you may wind up pulling out a few weeks later.



I just bought an '04 5. 9 HPCR with a 6 speed transmission on ebay for $4k. The combo has less than 10k miles on it. These motors are powerful and quiet . the wiring may seem complicated, but it actually is VERY simple. Not trying to tell you what to do, but it's something worth looking into.



There is a company that sells complete, brand new 5. 9's on ebay for around $5600. That's for an unfired, 305 horsepower motor. Not bad if you consider the cost of rebuilding a 12v.

 

[KellyClark]

By the way, my '04 5. 9, with the NV5600 6 speed trans weighs 1750 lbs. Not sure what a 4bt and NV4500 weigh. Hope that helps.

 

[THedlund]

Thanks for the input. I believe the 4bt is around 700lb which is close to the weight of the original bigblock. Did you have to upgrade springs and such on the front end of yours to deal with the increased weight of the 5. 9?