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Discussion Starter #1
I was wondering which vehicles (Early 70 to early 80s trucks or SUV style) were the "easier" ones to install these cummins engines in? I don't have alot of room or tools to do custom fabrications with so I was wondering what vehicles are done much more regular than others or parts or mounts can be bought premade?

What is a reasonable cost expectation to buy and build this? I would have to buy the project truck, engine, trans, and everything else to go with it. $5,000?


Thanks
Larry
 

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If you want a complete bolt in with very little fab work almost none actually, and low cost you need to start with the exact right truck. I don't know much about the chevy side of Fords I can help. After fabing my front mounts and making everything work together I would guess that the perfect truch for retrofication would be a 1987 to 1995 F-250 4X4 with the ZF 5 speed and powered by a 300 inline six. You would need the Ford engine and flywheel set up. The front motor mounts will sit directly into the 300 frame stands, the engine sits high in the stands but if you plan to use the stock H1C turbo you will have enough clearance to the hood. The trans will stay right where it is, I had to space mine up do to the low Dana 60 Front end but with the I beams your trans will not have to move. The alt wiring should match up. The only area you will need to do much fab work will be the exhaust, a hammer to the firewall will create the clearance neccessary for the down pipe and then its off to the muffler shop for the down pipe and the rest. IMO this woulod be the easiest swap to do. Cost though is anyones guess find the exact truck and cost will be cut in half. Good Luck hope I helped.

Check out my build thread to see the front motormounts and the trans xmember.
Mongos firewood monster truck
 

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Yes that did help. I actually prefer the older fords. I own a 78 F250 and read here before the 80s model fords are pretty easy to install. I will go look now to get an idea of what a good body late 80s ford will cost. I wanted a 4x4 also but it wasn't a must so this was also good to know.
 

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The older chevies are also a pretty easy fit, but will require some crossmember/mount mods as will most other chassis as well. The 25/3500s will handle the power and weight fine. However, the ford does have a leg up with the OD transmission. However, if you can get an engine with OD trans. as a combo the dodge stuff is stronger. 2WD will be a pretty close drop in, but 4WD is a little more involved. I used a chevy auto to reduce initial cost, but ended up spending the money to upgrade to auto OD shortly after so cost was the same in the end.
 

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I have never had the issue of a 4BT sitting up high in the 80-97 Ford truck 300 six mounts. I think if you had issues with this you were using the wrong rubber mounts, probably the first gen dodge biscuits instead of the breadvan industrial biscuits which are 1/2"+ shorter.

Plenty of downpipe room, no cutting or fabrication whatsoever, 4BT drops right in and bolts up 2wd or 4x4. The frame crossmember is identicle 2wd or 4x4 in these years.

Including purchasing the truck, the engine and all associated little bits and pieces like belt, hoses, tach interface, etc I've seen it done for about $3000.

Buying the right truck is the key. Get one with a small block or six, 5 speed and 3.55 gears and you're in business.

I think the Fords really lend themselves to these swaps because there is no cutting necessary and they are plentiful with good OD manual transmissions.

If you want to go with the 6BT I would start with a diesel or 460 truck for the stouter 5 speed.
 

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If you want to go with the 6BT I would start with a diesel or 460 truck for the stouter 5 speed.

I'd recomend one with a 460 over the 7.3 idi. I'm trying to swap one into a '90 w/ the idi and I ended up needeing a radiator/support from a truck with a 460 because there was just no way the engine was going to fit behind the huge idi radiator.
 

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I am using the HX35W turbo on the high mount exhaust manaflod, I had 1/2" clearance on my 86 F-350,with the 300 stands and org. mounts. The exhaust outlet of the turbo was very close to the firewall when I had it on the 300stands, There would not have been enough room for the down pipe. I used 1st gen Dodge mounts, 1/4" higher then the stock bread van mounts the engine ended up sittin 4" from the crossmember, Personal preference I fabed my own mounts and set the engine as low as I could get it into the frame, plenty of clearance now, even with the HX35W.



This pic shows the engine on the 300 stands and the ZF trans crossmember see all the area between the pan and the front crossmember.



This pic shows where the engine ended up after fabing mounts. I do not know much about the two wheel drive trucks, I just figured if your going to go thru with the swap it would be a 4X4. I personaly do not like the Mazda trans found in the 1/2 tons, thus the 3/4 ton pick as well as the 300 inline in the donor truck so that there will be very few changes to the truck. I think the 3/4 ton front ends will hold up to the wieght better anyway.
I found a 1988 F-250 light duty with the 300 six inline and the ZF 5 speed 4x4, I used the trans transfer tranny crossmember and the front drive shaft from this truck. It would of been a perfect starter truck for a conversion, pull the 300 out install the 4BT and away you go!
 

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I can see how the high mount manifold would get in the way.

With the stock breadvan mounts on the 300 stands and the tranny in the stock location the drivetrain angles are perfect. Dropping the front of the engine means dropping the tranny as well and throwing off all your critical U-joint angles. Not a major thing to overcome, but something easily avoidable by swapping on a low mount turbo manifold or running a chopped 6BT dodge manifold.
 

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Thats what is great about doing the swap, everyone can do there own thing. I have been looking for an exhaust manafold no luck yet I was going to put a mookheader kit on it, as a matter-a-fact its on the bench in the shop. As I said I had to raise the rear of the trans as well to clear the front driveshaft on the tranny crossmember all the angles on the u joints have remained very close to stock. remember I started with a 460 C6 combo so my transfer position is now completly differnet then when I started so I wasn't worried about not using the factory location of the engine. Still the Fords are the easiest to retrofit if you find the right truck to start with.
 

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You can always do it however you want, just seams like some swaps revolve around tossing an engine in however it fits or looks good and welding some steel to hold it there with no forethought to drivetrain angles.

Ford 4x4's are 5-5.5 degrees. You can't really change that. a 1/2 degree either way represents significant reduction in U-joint life that gets worse as a square function of the angle and increased vibration.

2wd's are more versatile in that the rear pinion angle is easily adjusted. 4x4's aren't as forgiving since changing the front pinion angle is a major undertaking.

If I take the trouble to swap a cummins in something I'm going to make darn sure I can lock the hubs in and drive 60 MPH for hundreds of miles and not worry about the front driveline U-joints turning to powder.
 

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I will measure my angles again to be sure, thanx for the measurement, I have a locker installed in the front axle so a 60 MPH trip with the hubs locked is completely out of the question, The truck only likes to go straight, driving in snow is fun as well, if your not in the throttle around a turn your not going to go around that turn, The locker has gotten me out of sticky situations though places an open diff would have big problems with.
 

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The frame zero reference is the lower lip of the frame just forward of the front rear spring hanger.

I just drive with the shortside hub unlocked with a locked front end.
 

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I will recheck them, you say 5* to 5.5* is normal? Is this for all the Ford 4x4's including the 350's W straight axle, My front axle is lower then a twin I beam axle which would give a different angle, right?
 

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No, the drivetrain angle isn't from the ground. It's in relation to chassis zero.

Using a good bubble protractor, not a cheezy angle finder measure the angle of the lower edge of the frame rail just forward of the front rear spring hanger on either side.

Then measure your engine angle. Subtract the chassis angle from the engine angle and that's your actual drivetrain angle.

The cheez welder's angle finders are only accurate to within a degree or two. No good for this work.

A degree difference is about an inch at the front or rear of an engine/tranny combo.
 

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OK in relation to chassis zero, I get that part, I have a text book that shows 4x4 working angles can go to 11* as long as the canceling angle is the same to cancel out the speed variations common to u jonts, any thruth to this in yout eyes? The text book also states working angles are mesured at each u joint using the centerline of the input or output shaft as 0 and the driveline as the measured angle? By the way we have successfuly hijacked this thread. Lets move it over to my build up thread? Mogos 4BT firewood monster.
 

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Discussion Starter #16
Does going with an older truck compared to a newer one any better? I was thinking of getting something around 1980-84 but I haven't made a definate decision on 4x4 or not. I saw a 80s model on ebay for around 1500 or less with the inline 6 with 4x4 and body seemed to be in good shape.

I was thinking older also because it seems to have less wiring to deal with than they do as the newer they get. I am also considering going Bronco and I guess the Broncos were build interchangable with the trucks?
 

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The Ford wiring is real simple. Ford was nice with thier EFI in the 80's and 90's and made it pretty much entirely seperate from the rest of the truck wiring. You can just cut it all out, hook up the oil pressure and water temp wires and everything works like it should.

A non-EFI truck would be simpler, but don't let the wiring scare you, it's not difficult. The newer trucks have overdrive transmissions, something nice to have with the diesel.
 
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