Our VE pulls just fine with heavy loads as well. I turned it up slightly, as I know how hard my sister can be on things. I don't have to take anything apart to turn it up either, just a few little adjustments...

 

Yes, but all you hear from the "coal roller" crowd, is how much of a dog the VE pump engines are.

I had rode in one many years back, when it was a fairly new truck. Can't really tell much from the passenger seat, but we had a rather large, heavy trailer behind it.

I forgot about this, but I did drive a D350 way back around 93/94. It was a dually, with a rather heavy work bed fully rigged for welding anything, anywhere a 2wd dually could get. That truck had ~50K on it, and I was picking it up from having the 2nd replacement auto trans installed. Needless to say, I drove it rather easy, so it doesn't really count.....

I have driven plenty of different cummins powered trucks, but to this day, not a single one that was a 12V & manual trans. I know how much better a 24V pulls with the NV4500 or NV5600 behind it, rather than an auto. So I hope to see the same kind of improvement with my setup.
Heck, I've even driven a 5.7L "Hemi" with a NV4500. I had to make sure the trans was ok, since it was a salvage yard unit. The old one was killed by lack of oil, while dragging a dual wheel tandem axle trailer......
Loved the trans, hated the gutless wonder under the hood. Still cannot understand why anyone would buy a dodge CC dually with a gas engine, rather than opt for a cummins, since that is the only reason to even consider a dodge/ram....... The owner of the truck borrowed the bosses 6.0 PSD powered F250 to drag that trailer back home 300 miles. He discovered just how much of a dog that "Hemi" really is........ The 6.0 would top hills at the same speed he had been going before hitting the hill, and he used less fuel on the round trip with it, than he did one way in the gasser......

 

I know they put the rotary down, but hasn't been my experience. They can run their mouth as much as they want, I know what I can do with ours. They likely would find it hard to believe I scaled in a load of scrap and rig at 24,500 with a NA 6.9 4 speed. I did notice quite a difference between when the 6BT was auto vs now with the manual. When I got it, the donor was a rollover. It seemed the rear brakes were dragging or something, because it was an absolute dog. In the F350, not as much a dog, but still a bit. Turned up the fuel a little, adjusted the smoke screw, and it woke up a bit. Then with the manual, it was quite a change. Started out with the A518, burned it up, tried the 47R, burned it up in 6 months. Put in the NV4500, been with it ever since. I had the advantage that the F350 had a ZF in it originally, so made it an easier swap back to a manual. I had just left the clutch pedal in it.

 

Good to know that it's not just my imagination that a manual trans seems to really wake up the output of these engines. I guess it's the slippage of the torque converter that makes a lot of the difference, though I would guess the auto consumes some power to operate, as most do.
I have no idea whether the fuel has been turned up on my pump or not. As such, I've done nothing more than clocking the factory fuel pin to the steepest part of the ramp, and replacing the flat blade screws with torx head screws. It was already apart when I got it, so I also inspected the rubber diaphram before reinstalling. I may have the timing advanced slightly too. No more than 2-3 degrees though.
If I want a bit more power later, I may replace the fuel pin and/or spin the star wheel down a couple turns. I'll just have to watch the boost and EGT levels. No waste gate, or intercooler........ The engine was originally to an auto, so I know it tuned on the lower end of scale. Should be plenty of room left for more, even without adding any parts.


Interesting side note. Right now, I am at around $2500 invested. I know I have another $500-1000 yet to be spent though. For the last couple years, I have been watching the asking price for both 4BT and 6BT engines. The 4BT's tend to be offered at $2500 and up, while the 6BT's can be found from around $1200 (VE) to $1500 (P) and up.
50% more engine, for ~50% less money......
Weight-wise, the 4BT is only ~20-25% lighter than the 6BT, and isn't much more than a 460 or 300.
As such, I find it odd that the 4BT is considered to be far more popular for swapping into these older trucks. Heck, even the IDI or 7.3 PSD is more popular than a 6BT as a swap candidate. Yet, it seems as though the 80+ Ford trucks were designed to accept the 6BT, even though it didn't come into existence until 84........

 

The 4BT is more about fuel efficiency I think. They tend to be a bit harder to come by as well. Also, the size makes them easier to do. Essentially, they are a 6BT missing two cylinders... I don't know as they are more popular though, as I know there are a lot of them out there, and most of the swap companies are typically working with 6BT swaps, not that there is a lot of difference for the parts.

 

Funny thing about a large portion of the 4BT swaps. A lot of guys will start adding performance mods even before dropping in the engine. This goes against the fuel efficiency thing completely. Some guys stop at about the same power/torque ratings that a bone stock 6BT has, while others will go even further.
It seems that the price of 4BT specific performance parts is higher than the same stuff for a 6BT, and it goes without saying that a 6BT will always out perform a 4BT with equal mods, and the 4BT will always be a bit shakier........

I guess the 4BT is a bit harder to come by, since the majority of the ones found set up for on-road use were retrofitted into existing chassis, while the 6BT was offered as a factory option in more than just one make/model.
I still don't see the need for paying that much more, for less engine. Granted, getting the right one can greatly simplify a swap, as well as reduce the final cost for doing the swap. Though the "1st gen" 6BT isn't that much harder to fit into one of these trucks, thanks to the way it was mounted in the original chassis......
If the 4BT was priced about the same, or less than the 6BT, I might have gone that route instead. Heck, I could have even used that same trusty old C6, though a GV OD unit would have been highly desireable........

 

I have heard most 4BT's are worse on vibration. I wouldn't understand why they crank them up to the level they could have just gotten from the 6. Sometimes, trends just don't make sense... Most of the 4BT's I ever see were typically mated to a GM trans.

 

Yes, the 4BT has a lot more vibration. It's the nature of an inline 4, compared to an inline 6. The 6 will almost always be much smoother, especially with the same bore/stroke.
It doesn't make sense to pay more for a 4BT, then up the power to match a 6BT, when the 6BT is usually cheaper to begin with.....

Yes, the 4BT is commonly found in both Ford and GM chassis "step van/bread truck" vehicles. They will have the matching bellhousing pattern, Ford small block, or GM, since they were typically retrofitted from a 300 Ford or 292 Chevy I6.

As Switchfoot showed in his swap thread, https://www.ford-trucks.com/forums/1...up-thread.html finding one from a Ford chassis, makes it almost a direct fit swap into a Ford truck, using the 300 frame stands, and a Ford trans. I think he bought a complete bread truck for less than most people pay for just a 4BT. His swap made perfect sense, as he hasn't tried to really hop-up the 4BT.

 

That is something I would like to do to my old 78 F150 shortbed, I don't want big power, I just want to be able to drive it on less fuel. The vibration isn't something i care to add in. It is a bit harder to get a 6BT in the older trucks like that.

I have heard mention too that the 4BT doesn't have a balance shaft, while the 6BT's do. That is the explanation for the excess vibration that has been given.

 

78 F150 huh. 2wd? If so, I have heard you have to channel the front crossmember about 2" to make room for the oil pan. 4wd doesn't have this issue.
With factory A/C, neither fits real easy. That is one rather large HVAC box to attempt to get the turbo to clear. Using something like classic air's all in one kit that fits completely under the dash, makes it much easier.
Otherwise, they fit about the same, though it is a tight fit between the rad and firewall with the 6BT, but it can and has been done.

No such thing as a balance shaft in either. Taking a picture of the gear drive under the front cover from a straight on angle, you cannot tell which is which.
The higher vibration in the 4BT comes from 180 degree crank rotation between cyls firing, as opposed to 120 degrees in the 6BT. Same reason a gas 4 cyl has more vibration than an inline 6 gasser, so many I4's use a balance shaft, as do some V6 engines (Chevy 4.3, for example). It's just the nature of the beast. 4 crank throws are just harder to keep stable than 6 are. As RPM goes up, the vibration becomes a bit less noticeable.

 

Mine is a 4wd, and factory air. I know they are being done with the 6Bt's, just quite tight. I don't have any readily available to me, but I do have a few 7.3 IDI's around... Thought about going that route. Probably end up just leaving it gas though, and go from the stuck 351M to a 351W. I have the motor and trans and mount towers to do that. Well, the mount towers are in a 2wd, so it might make for having to custom it a bit.

 

The 7.3L is much harder to make fit than a 6BT. Not only does the HVAC box get in the way, but so does the brake booster. Body lift is almost a requirement, though going hydroboost can help..... Or manual brakes, but who wants that sort of leg strain?

As for 351M to 351W swap, I'm not 100% sure, but I think the frame stands are the same. The W wasn't offered, but the 302 was, and I believe I read somewhere that the 77-79 "small block" frame stands were different than 69-76, due to Ford modifying them to also fit the 351M/400. As such, 77-79 302 motor mounts on the 351W, should allow it to sit right down in place.
I still find it amusing that 65-76 I6 and FE engines used the same frame stands, just different locations on the frame. I guess Ford decided "why re-engineer, when we can just relocate".....

 

From an engineering standpoint, it is common to re-purpose parts as much as possible, as additional part numbers = additional tooling+ additional inventory. The motor happens to be coming from a 79 2wd... Thanks for the tip!

Can't say I'm surprised the IDI would be tight, they are dimensionally huge... I haven't really read up on it much, as me level of being serious on that project is pretty low. The body is hosed, and at this time, I have no title. I have most body parts except a good box, and I don't care to go flatbed for it. Also, time and funds, as well as space, dictate that it waits.

 

My plans for this weekend took a dramatic change of direction. I had planned to spend most of the weekend working on this project.
However, Monday brought news that will impact me for quite a while. My father passed away. He would have been 76 September 14.

 

So sorry to hear. My condolences to you and your family.