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oldhaven
11-20-2006, 12:38 PM
I've been driving this for about a year after a 10 year project. Noisy but surprisingly civilized. Full width F250 8 lug front, 14 bolt rear, Ford F350 ZF 5 spd with np 205, Defender/RR coil suspension, 68 mph highway cruise at 1800 rpm. Not sure if it belongs here but it looks like a LR, and I have two more real ones so I qualify. Ron Franklin, Bowdoin, Me.

o2batsea
12-04-2006, 02:20 PM
There's room in there for a 6. Maybe the V10? Maybe have to move the rad to the cab roof for better fit! U GO BOY!

landi41
12-04-2006, 03:57 PM
Not sure if it belongs here but it looks like a LR, and I have two more real ones so I qualify. Ron Franklin, Bowdoin, Me.
Oh i'd say you belong allright.........Nice job, no 1/2 measures there with that driveline either.........:thumb-up:

TeriAnn
12-05-2006, 10:50 PM
I've been driving this for about a year after a 10 year project. 68 mph highway cruise at 1800 rpm

The engine has lots of fans but you are one of the few that seem to have experience with one. A few questions:

1. How much does the engine weigh?

2. What is the engine max cruise RPM? what RPM range is the engine happiest with?

3. What R&P ratio do you have?

What is your low range first gear ratio?

Thanks!

oldhaven
12-10-2006, 01:56 PM
Hi TeriAnn,
We spoke a bit about this project when I started it long ago, about the time your rig was in its second incarnation (or was it the third?) and it took this long since lots of (expensive) false starts happened along the way. I think I finally got it about right. It resembles the one-ton LR prototypes you can see in Lindsey Porter's book.

Thanks all for the compliments. I am pretty pleased and hope to make a few creature comfort improvements, like sound insulation, but is is well suited to its role as a work truck. I drive it nearly daily to work. I have used it in the woods quite a bit and it is quite literally a stump puller for me. I am not really into rock climbing or gettng lost in a mud pit on purpose. It is pretty light in the rear anyway with the aluminum bed (I can awkwardly pick the bed up by myself) so traction back there could be better. I will need to get a brake proportioner installed as the huge rear drums lock easily unless a light touch is used even though overall weight is pretty well balanced due to the engine position. (HydroBoost brakes with F150 power steering box run off an engine mounted gear driven hydraulic pump)

As for room for a Cummins 6. If a newer radiator panel from a Defender was used that would be quite possible, though this one seems to have all the power (torque) I need The 3.9 4BTA as used in boats can get 250 HP and huge torque. Mine is probably closer to 140, with 325 ft/lbs at 1876, which is 65 mph highway cruise in fifth OD. That is a happy point for the engine, and hills mean nothing. The non-automotive fuel pump works almost as a cruise control to maintain rpm with no pedal input, so I just watch the boost gauge and pyrometer. I hardly ever use first gear in high range as 3.04 second is a good starting gear.

The engine weighs 700 lbs more or less, while the cummins 6 is about 950, so that's another reason to avoid the bigger engine. It may vibrate a bit more, but I don't consider it unreasonable now.

Max comfortable rpm as my fuel pump is set is about 2600. It could turn 2800. I don't need that as I can do 70 with the 33 inch tires at 2020. 100mph is theoretically possible, but you won't see me there testing the theory. Axle ratios are 3.73. Final ratio in fifth high range with .76 OD is 2.83, final ratio in low range with the 5.72 first is 42.67 at which max torque is achieved at 4 mph and even at 2mph the torque is still above 200 ft/lbs. I have idle set at 750 rpm.

As for disadvantages, it does blow a bit of smoke when accelerating too quickly, (great for getting rid of tailgaters), and my dog can hear me coming a ways down the road due to the distinctive Cummins clatter and lets my wife know to expect me.

Ron

yorker
12-12-2006, 12:41 PM
what is your average mpg?

oldhaven
12-13-2006, 07:25 PM
I have yet to figure out the interface between the transfer case and the LR speedometer, so I drive by engine rpm for speeds. By watching the engine hour meter, guessing at average miles per hour run and how much and when I fill up the front and rear tanks I know I am getting over 20, but how much....???? If anybody knows of a way to plug two different speedo cable ratios into a black box and come out with correct speed and odometer I would appreciate knowing about it.

Ron

leafsprung
01-24-2007, 05:51 AM
ditch the speedo cable and get a norscogg gps speedo

slorocco
04-12-2007, 03:33 PM
What did you do with the front springs to fit the full width axles under there? I'm toying with some ideas myself but cant seem to get the full width stuff under there without outboarding the front springs.

J!m
04-12-2007, 03:48 PM
Get generic spring perches and weld them on to the new axle tube to align with the series frame. "Outboarding" the series springs does not sound like a good idea to me, and prevents you from ever going back should the need arise.

Also, keeping the springs inboard allows wider tires with no loss in turning circle. In fact, I'd almost bet your turning circle would be much improved over the stock series...

slorocco
04-17-2007, 01:51 PM
Get generic spring perches and weld them on to the new axle tube to align with the series frame. ...

Gee, why didn't I think of that :rolleyes: . All kidding aside, I'd have done that if it were feasible, but it cannot be done with full width axles. You'd have to weld one of the spring perches right on top of the pumpkin. Your two choices are to either shorten the axle width or outboard the springs.

J!m
04-17-2007, 02:08 PM
Yes, shortening one side of the axle to get the diff where it should be I thought was obvious, but perhaps not...

Fo those who don't know, you have to have all your drive line angles correct (diff input parallel to t-case output [most important] and side angle as close to zero as possible under the weight of the truck at rest [slightly less important]). If the transfer case output is outside the frame rail, then the pumpkin needs to be outside the frame rail (and your spring perch needs to be ON the diff, like the stock series nearly is). If the transfer box output is within the frame rails, the diff needs to be within the frame rails.

You want no angle to the side if it can be avoided- the drive shaft parallel to the frame rail (and it obviously can be in this case, since you are making it up custom), so set it correctly before you weld it, or have an axle made up the correct width with the diff in the correct place. There are several companies who do this sort of work, and this is what we refer to as "the right way" to set up custom rigs, if you simply MUST change out the axles. I'd suggest a set of Ford 9 inch front and rear, so you have the removable third member like a stock series truck for quick repairs (although they don't break).

Now the stories come pouring in of how "it's been XXX years since I did mine and it's fine" well, take the chance then. Meanwhile, look under any factory car or truck and see how the side angle is as close to zero as possible... Do you think there may be a reason for this? Hmmm....

slorocco
04-18-2007, 11:25 AM
Not looking to get into a discussion of what's obvious or not. OldHaven stated he was using full width axles, not narrowed axles, hence my question to OldHaven on what he did with the springs.

oldhaven
04-25-2007, 06:33 PM
changed to coils and redid the mounts inboard lined up with standard 110 upper mounts

oldhaven
04-26-2007, 06:17 PM
No mysteries, just a lot of welding and fitting

Rovah
06-16-2007, 11:46 PM
Ron, great to see that thing done. Looks sweet. Considering a diesel swap into my IIA at present.

Cheers! John

Saxondog
01-21-2008, 10:18 PM
I've been driving this for about a year after a 10 year project. Noisy but surprisingly civilized. Full width F250 8 lug front, 14 bolt rear, Ford F350 ZF 5 spd with np 205, Defender/RR coil suspension, 68 mph highway cruise at 1800 rpm. Not sure if it belongs here but it looks like a LR, and I have two more real ones so I qualify. Ron Franklin, Bowdoin, Me.

Just got a 109 wagon, have been mulling over what to do to my new project. I have 2 generation 1 6BT dodges, a 1990 D350 dually 5 speed and a 1980 crew cab 4X4 currently undergoing off frame resto and conversion to the Cummins. I had been thinking about the 4BT for my next project the 109 Landrover. I see it's been some time since this thread was moving. Have you learned your MPG, I get 21 with the D350 dodge of mine. I figured the 4BT would do some better. Any other thoughs on your conversion. I want to do wider axles also, but though fullsize PU stuff would be too wide but yours looks good.

mongoswede
05-17-2010, 02:38 PM
working on a project to put a pair of Dana 44 axles from an International Scout II (1980) under a 71 series III. planning on running a T18 or T19 4 speed with a Dana 300 transfer case...engine to be determined...might stick with stock for now. The R&P in the axles now are 2.72:1 which not going to work with a stock engine. I can get a plethora of R&P's for the Dana's though so no worries. The axles are a couple inches wider then the stock rover axles and the rear is a center drop instead of a passenger drop. To make the rear fit I just have to relocate the spring perches. To make the front fit without shortening the axle we have to widen the front spring mounts slightly....about 1.5" per side outboards. This is not so bad.

Ideally I'd like to get a set of axles built to fit from either Moser or Currie but they are not in the budget at the moment.

The nice thing about the 76 and later scout axles is that they are disc brake up front and there are tons of parts for them...plus they are very durable compared to stock.

J!m
05-17-2010, 04:26 PM
Sounds like a nice project!

Just add the Defender fender flares and it will look pretty 'socially aceptable' as well!:thumb-up:

Maryland 110
05-22-2010, 10:14 PM
full coiler,galv chassis,4bt, hcpu. this thing is fawking cool !
nicely done.

oldhaven
12-27-2010, 11:12 AM
Russell Mountain, Breakneck Ridge, Blanchard, Maine

msggunny
12-27-2010, 12:26 PM
Russell Mountain, Breakneck Ridge, Blanchard, Maine

Nice shot.

Great truck by the way.

Tim Smith
12-27-2010, 11:31 PM
What a great build!