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I have a 1984 Ford E350 extended length raised roof camper van. It weighs around 8K lbs. It has a 6.9/Banks in it right now and gets about 13 mpg. It has one of the more sloping fiberglass tops, not the ones that are built like a sail. It has either a bad HG or the dreaded Navistar cavitation holes. I plan to remove the heads soon. If it has cavitation holes I want to consider a 6bt or 4bt swap. I searched this forum and could not find anyone who has done it. Obviously a 4bt will fit more easily. I don't want to end up with something that is too difficult to work on. Will the 4bt move a vehicle this large? I think my 6.9 has about 200hp with the turbo and it is plenty for what it is used for. Any experience/advice? What kind of fuel economy do you estimate a 4bt would deliver in a vehicle like this? I have done 6 major engine conversions before so I am fairly confident I can do it.

Brian Roth, engineconversions.org
 

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I wouldn't recommend towing anything over the combined GVW for that vehcile. Say it's GVW is 8600 and it only ways 6600 lbs. That'd leave you roughly 2k for a trailer. As the weight goes up, the efficiency of that 4BT is going to go down, not to mention acceleration times. Mileage in a vehicle like that (You didn't mention what tranny, so i'll assume an Auto) will probably be in the high teens low 20's at best.
 

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Discussion Starter #3
That kind of mileage would be 50% better than what it gets now. What is the highest GVW for which a 4bt is suitable for comfortable highway cruising? It seems that 6bt's can move 25k LB busses so I thought a 4bt might move my van. Perhaps my logic is faulty.
Brian
 

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I'm considering a 4BT for my '87 E350 4x4 cargo van(138 WB). It currently has a 351W/C6. I'd be putting in a 4BT with a non-OD 5 speed(3.54 r/p and 33-35" tire size). I'd be happy to get 20 mpg but I think with where I use it(55 mph top speed) I might squeeze a few more mpg out. I figure with the altitude it's operated at, the 351W is not giving me any more than what a stock/mild 4BT could. If your turbo'd 6.9 is enough for you a modded 4BT could do it.

I like the IH IDIs but they don't give great mpg. With an early turbo'd 6.9, my bet would be on headgasket, not cavitation.

BTW, I think the Ford stepvan setup would be a bolt-in to a conventional E350, if from an older stepvan that would've used the same chassis design. I don't know when changeovers with the E series chassis occurred. Doesn't sound like that's much of an issue for you anyway but it might be one of the easier swaps.

Ken
 

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Discussion Starter #5
Thanks for the insight. My van is an 84. What kind of front end do you have? Is yours a pathfinder conversion? Quadravan? I pulled my driver's side head off yesterday and do see evidence of a blown HG. So at this point I'd guess it's not cavitation holes but I need to get the other side off and do further diagnosis. So there were some step vans that used the E series chassis? What years?
 

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I wouldn't recommend towing anything over the combined GVW for that vehcile. Say it's GVW is 8600 and it only ways 6600 lbs. That'd leave you roughly 2k for a trailer. As the weight goes up, the efficiency of that 4BT is going to go down, not to mention acceleration times. Mileage in a vehicle like that (You didn't mention what tranny, so i'll assume an Auto) will probably be in the high teens low 20's at best.
isn't GCVW more important for towing than GVW? Say A 3/4 ton ram with a 6bt has a GVW of 8800lbs, say it ways 6600lbs, i would hope it can tow more than 2200lbs.

Or am i not reading your statement correctly?

Are you just saying for that particular vehicle, not in general? I would agree with that, for a vehicle that large towing with a 4bt wouldn't be ideal, at least not heavy and regularly. Having a GCVW over 8600 with a 4bt is fine if you ask me though.
 

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Well to add to the mix. The bread van I bought off dovebid is a ford e350 chassis (grumnan 18') with a 4bt/t19.

When I drove it, it would easily run up to 55mph and slowly finish at 65mph, stock.
On hills 6% grade, it slowed to 55mph.
I would not worry about it.
MPG =? fuel gauge broken... only drive 150miles and parked.
This is the setup I am going to use for my 53GMC repower.
 

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isn't GCVW more important for towing than GVW? Say A 3/4 ton ram with a 6bt has a GVW of 8800lbs, say it ways 6600lbs, i would hope it can tow more than 2200lbs.

Or am i not reading your statement correctly?

Are you just saying for that particular vehicle, not in general? I would agree with that, for a vehicle that large towing with a 4bt wouldn't be ideal, at least not heavy and regularly. Having a GCVW over 8600 with a 4bt is fine if you ask me though.

You only subtract tongue weight from the GVWR when you consider towing. Most single wheel HD pickups are rated from 8600-9900 GVWR. The majority of those can tow 12k on the hitch with the proper equipment with no more than 10% of the trailer weight on the tongue.

So, that being said if you've got a 6600lbs Truck you'd subtract the GVWR (8600) minus the Vehicle weight(6600) and that leaves you 2000lbs. Subtract the tongue weight of the trailer (say 1000lbs) and that leaves you 1000lbs for Gas, Gear, Passengers, etc.

I think you're confusing
Gross Combined Weight Rating (GVWR + Towing capacity)
with
GVWR(Gross vehicle weight rating)

Since we're talking about a 4BT - most folks are moving less than 11000lbs total weight (approx the GVWR of a P30 van with a 4BT). That's vehicle weight + trailer weight etc. Anything more than that and I'd think the 6BT would being to take a preference due to saftey and driveablity issues. He's got an 8000lbs rig. Thats pretty heavy to start with - with performance in mind, I mentioned the 2k trailer figure. From reading on the site here, most folks have a fairly light rig that their 4BT is in (4000-7000 lbs) and it seems to do pretty good.

It appears that that E350 has a GCWR of around 20K (Vehicle + Trailer). If loaded he weighs 8000lbs that leaves him with 12000lb for a trailer. Would you ever want to move 20,000lbs with a 4BT? Maybe, but not me. It's not safe IMO. I like some backup power if I need to pass someone or accelerate into traffic from the on-ramp.
 

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...What kind of front end do you have? Is yours a pathfinder conversion? Quadravan?
... So there were some step vans that used the E series chassis? What years?
Mine has a Dana 44. The stock front-end was rated at 3500 lb and thus the conversion company put in a 3550 lb rated Dana 44. I wish it were a 60 but it works.

It's a Trail Master All Wheel Drive by Trans Axle of Colorado, Inc. Some parts of the conversion are nicely done others not so nice.

I don't know what years of Ford stepvans used the 4BT. I have a couple of Hercules engines from '83 Ford E350 chassis.

Ken
 

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I think I am about to do the 4BT swap on my newly acquired 2000 E350 4x4 Quigley van and I'm thinking the only way I can get the gearing and the mileage I want is to run a diesel geared C6 and a separate overdrive between the 1356 T-Case and the C6.Low on the first half with the C6 and the low geared ring and pinion and long legged once I shift into overdrive(20-30%).


Anybody here have experience running an old fashioned setup setup like that with a 4BT?
 

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...diesel geared C6 and a separate overdrive between the 1356 T-Case and the C6...
Any particular reason for the OD being between the trans and transfer? Or do you have a model of OD already under consideration that is for an intermediate location vs final? I assume that the simplest place for an auxiliary OD would be after the transfer case.

Also, while I appreciate the reputation for longevity of the C6 in my van, my understanding of them includes the fact that they are not the most efficient non-lockup automatic out there. If maximizing vs just improving mpg was on the list of wants, I'd think a lock-up type auto trans or a manual would be in order. A transmission change could then encompass an OD.

Basically I'm saying I'd seriously consider finding a transmission that has the desired gearing vs money spent on putting an OD behind a C6. Especially so considering an engine swap is taking place as well.

I think the 4BT into an E350 is a great swap to do if regular trailer pulling is not in the plan.

Ken
 

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Any particular reason for the OD being between the trans and transfer? Or do you have a model of OD already under consideration that is for an intermediate location vs final? I assume that the simplest place for an auxiliary OD would be after the transfer case.

Also, while I appreciate the reputation for longevity of the C6 in my van, my understanding of them includes the fact that they are not the most efficient non-lockup automatic out there. If maximizing vs just improving mpg was on the list of wants, I'd think a lock-up type auto trans or a manual would be in order. A transmission change could then encompass an OD.

Basically I'm saying I'd seriously consider finding a transmission that has the desired gearing vs money spent on putting an OD behind a C6. Especially so considering an engine swap is taking place as well.

I think the 4BT into an E350 is a great swap to do if regular trailer pulling is not in the plan.

Ken

if you put the OD after the transfer case you couldn't use it in 4wheel drive. Not that you should be on OD really in 4wd, but if you accidentally used it, you'd most likely blow something up.
 

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Any particular reason for the OD being between the trans and transfer? Or do you have a model of OD already under consideration that is for an intermediate location vs final? I assume that the simplest place for an auxiliary OD would be after the transfer case.
That's it,I already have a an overdrive that's made to go between a C6 and a 1356 T-Case and it's a beefy looking thing that's guaranteed to hold up to towing in overdrive.I was told there were 2 versions both a 20% and a 30% but I don't know how to tell which one I've got but either way I'll be happy since I only have $1,600 in the whole setup including a built to the max diesel C6!

Also, while I appreciate the reputation for longevity of the C6 in my van, my understanding of them includes the fact that they are not the most efficient non-lockup automatic out there. If maximizing vs just improving mpg was on the list of wants, I'd think a lock-up type auto trans or a manual would be in order. A transmission change could then encompass an OD.
I'd like something less "slushy" than a C6 but longevity and robustness while still working in concert with the space and location of my 4x4 converted driveline are limiting me to automotive type transmissions and a manual would be great but too troublesome to figure out in a van.The C6/Overdrive/1356 T-Case is a perfect fit.

Basically I'm saying I'd seriously consider finding a transmission that has the desired gearing vs money spent on putting an OD behind a C6. Especially so considering an engine swap is taking place as well.
There is no automotive(smaller)transmission available that would fit and perform as you suggest that does not have a computer.I have decided that I will never,ever,ever have a computer regulating the functions of my vehicle's engine and transmission ever again after 20 years of computerized misery in everything from a Chevy Duramax pickup to a Volvo 670 Semi costing me thousands of dollars to fix and even leaving me stranded by the side of the road in the middle of nowhere (more than once) I wouldn't take a computerized transmission vehicle for free at this point and my interest in building a mechanically injected vehicle with a decomputerized drivetrain basically stems from a well earned hatred of solenoid and gizmo laden vehicles.Hell,I'm even considering installing an air starter if I can find a place to strap a tank without it sticking out like a sore thumb in my van
:idea:

I think the 4BT into an E350 is a great swap to do if regular trailer pulling is not in the plan.
I'll admit I'd like to see one of those 6BT E350 conversions in person so I could see if a similar system could be shoehorned into my 4x4 Quigley van then maybe I could do some occasional heavier towing but a 4BT can be tuned hot enough to pull around my Jeep on a small trailer or a couple of jetskis or whatever so I won't cry about the smaller engine especially when a similarly converted van is getting 25-28MPG unladen according to it's owner:eek:



Here's a 6BT in an old E350
http://www.youtube.com/watch?v=mEAWBRaol5E&feature=RecentlyWatched&page=1&t=t&f=b


Here's the only enginebay shot of another 6BT van
http://i71.photobucket.com/albums/i143/muttfj45/IMG_2023.jpg

If I could get a look at how far they had to move the drivetrain back to get that sucker in there I'd step up to a 6BT in a minute and put my 4BT in my wife's Landcruiser instead.
 

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Manual trans in an E350

I'm considering a 4BT for my '87 E350 4x4 cargo van(138 WB). It currently has a 351W/C6. I'd be putting in a 4BT with a non-OD 5 speed(3.54 r/p and 33-35" tire size). I'd be happy to get 20 mpg but I think with where I use it(55 mph top speed) I might squeeze a few more mpg out. I figure with the altitude it's operated at, the 351W is not giving me any more than what a stock/mild 4BT could. If your turbo'd 6.9 is enough for you a modded 4BT could do it.

I like the IH IDIs but they don't give great mpg. With an early turbo'd 6.9, my bet would be on headgasket, not cavitation.

BTW, I think the Ford stepvan setup would be a bolt-in to a conventional E350, if from an older stepvan that would've used the same chassis design. I don't know when changeovers with the E series chassis occurred. Doesn't sound like that's much of an issue for you anyway but it might be one of the easier swaps.

Ken
Ken,

I picked up your thread performing a search, and was curious if you followed through with putting a manual transmission into the E350 van in this thread.

I am very interested to know how this worked out for you, what parts you used: pedals, steering column, trans, t-case..etc.

Thank you in advance,
Chris
 

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Pengyou,

Have you started your project, I recently purchased a 1984 Ford E350 Cabriolet Van/Truck and I am wanting to replaced the 460 gas V8 with the Cummins 4BT?

Cliff
 

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I know some of the early 80's ford vans came stock with a manual trans. I had an old guy for a customer that had I think a 84 E150 that had a three speed manaul in it that was stock.
 

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i saw some swaps in older e350 vans from the 80s and even some from the 90s, using the 4bt and manual transmissions out of brazilian f350s and 550s... but the floor-shifter demanded some workarounds that i dislike... i prefer the collumn-shifters because it retains more space in the cab for the driver...
 

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I put a 4bt in my89 quigly with a zf 5 speed, worked great for 20,000 miles but the install is tight. I had a Dana 44 and had to notch the cross member and trim the pan so the doghouse would fit. Vans front frame rails started twisting so I pulled the motor and sold her, 4bt is now in my 74 bronco. I think it would be great in a e-250 or350 I wouldn't waste the time or money on a c6 trans use a zf. Ken
 

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I put a 4bt in my89 quigly with a zf 5 speed, worked great for 20,000 miles but the install is tight. I had a Dana 44 and had to notch the cross member and trim the pan so the doghouse would fit. Vans front frame rails started twisting so I pulled the motor and sold her, 4bt is now in my 74 bronco. I think it would be great in a e-250 or350 I wouldn't waste the time or money on a c6 trans use a zf. Ken
brazilian f350 and f550 are offered only with zf 5spd manual transmissions...
 
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