6.9 liter IDI in 1976 ford

[tyre25]

Hello everyone! First post, so I figured I'd kick it off with a question!

I have a '76 F-100 that I was thinking about putting a 6.9 IDI with a 5-speed into.

Here was my plan, buy a HD four core radiator (the one for my 302 barely keeps the truck cool as it is) replace the fuel tank with a new, 38 gallon tank, stainless steel lines all around, painless wiring harness, etc, etc, etc.

Now, here was my thinking: the trucks that came with these engines from the factory also carried 460's. LMC carries simple (but complete) mount kits to put the 460's into the '73-'79 F-100/F-150's.

Given how much more these blocks of iron weigh, I was thinking of maybe using the air bags that fit into coil springs to help take the weight and retain camber. (it's 2WD, Hooray twin I-beam!)

Would these mount kits work with the diesel engine? Would they require any serious fabrication besides the tranny mount?

How well do air bags hold up? Are they reliable?

And how will I get the speedometer in the truck work with the new tranny?

Would it be hard to change my truck to a hydraulic clutch set up?

Any thoughts are appreciated!

Thanks

Jonny B.

 

[h2odrx]

welcome to the site! do you just like the truck or you like the diesel?

 

[tyre25]

I really love the truck, (it's my second '73-'79) but I want a diesel. Power, reliability, mileage, longevity and being able to use alternative fuel sources are among my reasons for wanting diesel power. I would like a 4 cylinder Cummins, but I'm thinking it would be easier (hopefully) to install an IDI diesel.

 

[Diesel JD]

I'd imagine it can be done. The 70s trucks were really overbuilt from what I hear and what I've seen. Some folks have them in Broncos, so I'd think if they can handle a 6.9 so should an F100. The motor mounts are diesel specific. You need to get them from the donor vehicle. The 6.9 weighs around 1100lbs with accessories. It probably won't get the mileage that a 4bt would get but in a 1/2 ton application, driven easily with an O/D tranny 20mpg should be easily obtainable. What transmission is behind the 302? T18? NP435? These guys can handle the 6.9 but need a diesel specific bellhousing, and of course then you have no O/D ):

 

[Agnem]

We've got a few guys here who have already done your project. I suspect they will chime in. I think there is one other guys with a work in progress. We do have some experts here on this swap.

 

[tyre25]

Diesel JD,

302's from that era had two 3-speed manual transmissions to choose from. The standard one was the 3-speed Toploader. The other was a heavy duty Borg-Warner with a pretty deep first gear.

The three speed Toploader has a seriously tall first gear. I'm worried about clutch life and lugging the engine. I had a hell of a time driving that truck from N.C. back home to Vermont.

While I'm sure that how the mounts bolt up to the engine are different, I was thinking of using the mounts perhaps as a starting point. Maybe they could be altered to bolt up?

While the 4bt Cummins would be an ideal swap for what I'm looking for, the 6.9 might give me a whole lot of get up and go.

Real dual exhaust is also a bonus, and I can imagine that'll make one sweet sound!

 

[92F350CC]

Are you going to turbo it? I hear that it takes some shoehorning to get a turbo on in this bodystyle.

 

[tyre25]

I was thinking that by the time I could afford to do a turbo, I'll be out of school (Go UTI!), and back home, so I'd be looking at fabricating my own turbo setup. But I'm really building this truck with the idea that I won't have to replace it for a very long time, if at all. FS-2500 filter, coolant filter and lots of hopefully useful additives to stretch the life of this machine.

The truck is in great shape. It came from California to North Carolina, then I bought it after getting out of the Marines and drove it North. I think I'm gonna Rhino-line the whole undercarriage before I paint it.....

 

[Diesel JD]

The big problem with turbochargers on the 70s body style is the clearnace of the firewall, which is a problem for all Ford trucks until they made them with a turbo in mind(PSD) Yes Ford had some IDI turbo trucks but their solution was pretty lame in my opinion. I'd say you need a T18/19 or a ZF5 or maybe NP435.

 

[h2odrx]

Got any pictures? how long ago where you in NC? Thanks for your service HOOO-RAAAA!

 

[tyre25]

Here you go!

Not a bad deal for $1,300.

 

[h2odrx]

SWEET!!!!!!!!!

 

[CESMITH]

1st choice 4bt would make a nice high MPG truck either way you will have to buld mounts. stick with the t19 or ZF5 $.02

 

[6xCrew]

And not to knock the IDI since that is what I am trying to put in my 76 but the 4bt is about half the weight of an IDI. If I had had as easy of access to the 4bt as I have to the IDI and if my truck was not going to me some 12-14k pound rig I would have gone 4bt. I think about it anyway.

In a truck the size of yours you might get away with better than 30mpg. Something we IDI guys can not touch. If you do put it behind a nice 5sp and take advantage of that overdrive.

Calvin

 

[tyre25]

I agree, the 4bt would probably be a great motor for that truck and what it's normally used for.

How much of a difference in power are we talking about between the two engines?

I'm not really looking for a stupid powerful motor, but if the motors can have similiar life expectency, a little more oomph would be nice.

I wonder, if I have to fab mounts for everything anyway, if there's anything stopping me from running a John Deere diesel. The ones with the SAE bellhousing.........hmmm......