Full tilt front end.

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wildcatjason

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Have you said what year step vans this set up is from??? I'm thinking the ultimate set up with this would be, low rear gears, like 4.10's, the 4BT and a 4L80-E with OD cuz I'm sure this diesel like most, don't like high RPM's. But imagine the torque with the 4.10's and motor putting out 410 ft lbs. You can get a stand alone OEM computer for the 4L80-E that came behind the 6.5. IIRC, and someone can correct me if wrong, 92 and 93 year model 3/4 and 1 tons got it.

The engines parallel with the 6bt as far as years. Mine is a 1990 block but it was in a 1986 stepvan. They are still using these engine today. They are just computer controlled. People who run low gears usually do with big tires. Even the stepvan i owned had 4.10s with huge tires. I don't recall the diameter. I wouldn't call the 4l80 the ultimate if your looking for towing and gas mileage. Yes it has an overdrive, but it also has a 2.48 first. The problem with getting a standalone from a 6.5 diesel is the torque curve is different. Some guys run a optishift controller to change the shift pattern on the fly. A 4l80 would be great in a comfortable suv you don't worry about shifting and pulling a reasonable size trailer. I like my 3.42 rear and my zf5. It has a 4.10 first with an overdrive. Some guys who run the nv4500 say the first is pretty worthless for daily driving. Allison 1000 is an option as well.
 

HotRodPC

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If the Allison is an option, I'd probably go with that then. But, 2.48 first isn't all that bad with low rear gears, and you don't have a big gap between gears either. You have a tighter closer ratio in the 4L80-E than you do many other transission choices, like the 700r4 (4L60-E) and the Early NV4500. How about the Aisan auto OD trans? I'd imagine that is an option too since it's OEM behind 6BT Dodge motors.
 

wildcatjason

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I would rather have the best of all worlds with a deep first and a high overdrive. That's my feelings anyway. I don't think the Aisin from behind the 6.7 will work. I believe changes were made and I don't know of an adapter for it but I could be wrong. Here is a website popular for different adapters. I know all the 12/24 valves will work. www.destroked.com or www.fordcummins.com. I use destroked I've read it's better quality. Of course you just use what is in the stepvan.
 

wildcatjason

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Just an update:
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Picked up the gem of a turbo. I've read this is the one of the best turbos you can get for 4bt. It was only available for 2 years and are kinda hard to find.

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fan and overflow installed.
 

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Quite an intruiging project to say the least. The Turbo 4BT, and the tilt nose.... Really makes you wonder where this technology was back in the 80's. Great for economy, great for emmisions, may not be fast, but plenty of tow power etc, and back then the speed limit was only 55 so speed wasn't a huge factor anyway. What's not to like about it???
 

wildcatjason

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Ive had it up to 80 when the 4bt was stock and still had throttle. Acceleration wasn't there though. It should be a little better when she's back on the road. This turbo will spool much faster. This was a 4l60. Now it's a ford 5 speed. Might as well throw that in the conversion mix.
 

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Ive had it up to 80 when the 4bt was stock and still had throttle. Acceleration wasn't there though. It should be a little better when she's back on the road. This turbo will spool much faster. This was a 4l60. Now it's a ford 5 speed. Might as well throw that in the conversion mix.

Yuck !!! Which Ford 5 speed? As in the 90's model half ton manual transmission with the internal slave cylinder??? It's an OK transmission, but it does like to eat synchros and the slave is a royal bitch to change since you have to pull the trans, for just replacing a slave anyway. It's nothing more than the Mazda 4cyl transmission, and said to have a bit bigger bearings, but still the same shaft sizes. I was all loving this project till had to start throwing around 4 letter F words. 1 exception to that rule is 9 inch rear axle and I refer to it as that, a 9 inch, not a F$#% 9 inch. :rofl:
 

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wildcatjason

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Yuck !!! Which Ford 5 speed? As in the 90's model half ton manual transmission with the internal slave cylinder??? It's an OK transmission, but it does like to eat synchros and the slave is a royal bitch to change since you have to pull the trans, for just replacing a slave anyway. It's nothing more than the Mazda 4cyl transmission, and said to have a bit bigger bearings, but still the same shaft sizes. I was all loving this project till had to start throwing around 4 letter F words. 1 exception to that rule is 9 inch rear axle and I refer to it as that, a 9 inch, not a F$#% 9 inch. :rofl:

No.. It's the f350 zf5-s42 it came behind the 7.3. It has an external slave and has the best gear ratio set for this engine. F150 has two transmissions in the 90s. One is a version of this tranny with a internal slave and a different gear set and the other is the Mazda transmission your referring too. People run those as well. If it makes you feel any better ford didn't make it zf transmissions did. I don't get into brands. I've owned a little of everything.
 

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As a matter of fact, I don't like that. Cummins belongs in American Made Trucks. WTF???
Although, I have to say, VW made a hell of 4cyl diesel back in the 80's. Rabbits had them so the did the VW trucks. Hard to kill once they got a couple small issues ironed out of them.

You realize there is very little about cummins that is American. When I pulled my 1990 engine apart that has never been opened. The bearings had the cummins stamp with made in Great Britain on the back.
 

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No.. It's the f350 zf5-s42 it came behind the 7.3. It has an external slave and has the best gear ratio set for this engine. F150 has two transmissions in the 90s. One is a version of this tranny with a internal slave and a different gear set and the other is the Mazda transmission your referring too. People run those as well. If it makes you feel any better ford didn't make it zf transmissions did. I don't get into brands. I've owned a little of everything.

hahahaha, I still own a Ford, shhh. I'm fairly certain, I know which trans you're reffering to then. Just so long as its not the Mazda trans.... been to hell and back with those in several of the Fords I owned and drove for work trucks.
 

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Yeah I'm hoping this drivetrain takes me well into the truck having antique tags.
 

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So if this is just the same Cummins bellhousing pattern as in the Dodge trucks, then isn't it possible to run an NV4500 also without needing an adapter and special flywheel??? I'd imagine there is an assload of research to be on one of these with several options. I sure like the idea of the 4bt, but isn't much easier to find a 6bt since they are obviously more common??? As much as I'd love to do something like this, I'm sure it's the fundage that would keep me from doing it.
 

wildcatjason

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cummins 3.9 4bt
So if this is just the same Cummins bellhousing pattern as in the Dodge trucks, then isn't it possible to run an NV4500 also without needing an adapter and special flywheel??? I'd imagine there is an assload of research to be on one of these with several options. I sure like the idea of the 4bt, but isn't much easier to find a 6bt since they are obviously more common??? As much as I'd love to do something like this, I'm sure it's the fundage that would keep me from doing it.

In the ram there is an adapter between the nv4500 and the 5.9. Honestly the 4bt costs about the same as a 6bt. Just depends on what your putting it in as far as physical size and what your going to do with it. You can pick either up with 100000 miles for 1500, buy a reman. for 6-7000, or just buy a whole truck and scrap it. Yes I have done a ton of research. 2 years worth.
 

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