View Full Version : cummins 6bta Diesel Wagoneer Project
FSJeeper
12-05-2007, 06:36 AM
Down to final decisions before I start pulling the stock drivetrain out of my 91 Wagoneer Project. I have been emailing my diesel guru buds at the various diesel swap pages as well as having a final discussion and debate last weekend with our Texas FSJ diesel authority who pioneered the FSJ GM 6.2/6.5 and 6BT swaps years ago. The 6BT FSJ has been his daily driver ever since then. He recently sold his Cummins M715 which is up north now. I have been very lucky to have been a part in all of the several FSJ diesel swaps that were done in his shop.
Final decision is that I am going with the Cummins 6BT instead of the built GM 6.5 I have. His recomendation was an automatic but I prefer a standard so I am going with a NV4500 and a NP205. The Cummins 6BT I have has only 60K miles on it. I am mildly upgrading the turbo to a HX-35, upgrading the injectors, and modding the injection pump a bit. Should pull 250hp out of it and still get excellent fuel mileage with it. It WILL NOT be intercooled. Don't need it for this specific application based on my experience now with early Dodges.
I bought a 91 Dodge Cummins truck for the donor for this project but am using a different engine I have that is basically new. I have driven this truck a lot now and have a 2004.5 Dodge Cummins truck to compare it to. Yes, the 24 vavle Dodge has more HP, but the 12 valve torque comes on so soon and stays flat at lower rpms. Very driveable. Plus it gets excellent fuel mileage which I can not say for my 24 valve truck. In short, the 12 valve is perfect for my needs in the Wagoneer whos focus will be a daily driver and hopefully a fuel mileage king.
Willie has pre-engineered the swap and all of the details which have been test proven for many miles and years on the road and totally insane offroad thrashing as well as competition tractor pulls. If the Cummins could survive that guy, it will have no issue for me in this project.
I bought another set of the early Dodge Dana 61/71 axles with the 3.07 gearing in them for this. They are exactly like the set I bought for the crewcab.
I know that on very rare occasions I have been known to change my mind, but I think I am settled on this direction. I am open to any other ideas before I start tearing out the stock Jeep drivetrain.
PICS of the project wagoneer:
http://froadin.com/pascal/wag/
Lindel
12-05-2007, 06:41 AM
That's a sweet Waggie Pascal.
The main concern that I would have would be beefing the front suspension enough to take the weight of the 6BT.
etjeep
12-05-2007, 06:51 AM
Sounds like a sweet project. I agree with Lindel's comment on the weight issue, that would be my concern as well. I guess you have the spacing worked out in the engine bay. Must be very tight. I will be following this build. I would like to build a DD like this some day.
710 Burner
12-05-2007, 06:54 AM
Talk, talk, talk. Where's a wrench?? :rolleyes:
FSJeeper
12-05-2007, 07:15 AM
That's a sweet Waggie Pascal.
The main concern that I would have would be beefing the front suspension enough to take the weight of the 6BT.
I am going to start with Willie's recipe cause it worked so well for him for years with zero issues. Willie used STOCK M715 springs with one leaf removed. He bead blasted them, painted them in lubriplate, and put nylon sliders between the leafs. His M715 rode very nicely. If it is too harsh for the wagoneer, I'll take another leaf out or jest get some custom springs made.
FSJeeper
12-05-2007, 07:17 AM
Talk, talk, talk. Where's a wrench?? :rolleyes:
Most people do not plan to fail, they fail to plan. I am in the planning stage.
N2Jeeps
12-05-2007, 09:02 AM
FS Jeeper
I obsessed on every part of my project from the drive train down to which flared fittings I would use on the fuel system. You need to plan like this to make it a successful project.
When I finished mine she started the first time I hit the button and has never thrown a code. Proper planning will make all the difference.
That is one clean GW and should make an awesome project!
Tony - N2Jeeps
will e
12-05-2007, 10:00 AM
I have to hand it to you, that is a challenge I don't think I could take on. And yeah, you need to have a well thought out plan in place. Sure, it will take a turn now but with something this complicated, a good plan is a must.
addicted
12-05-2007, 10:10 AM
You should pull down mid 20's at the very least with those gears and an overdrive. They used those gears behind the 727 auto's and 3:54's in the manuals with the Getrag. I get 20 or better depending on the fuel I can find for my 92' extended cab W250 with an A518 non lock-up auto, 3:54's and an NP205. I used to average 22 mpg before the ULSD was everywhere.:banghead:
The last time I came back from my parents in S.C. I found a Texaco with B20 and got 22mpg on the freeway running 75mph that kind of speed usually nets me 19 mpg at best with an almost 8000 lb truck.
I do the love the power and growl of the mighty 12V Cummins. Now if only I can stumble upon an NV4500 for cheap, (and when I have the money) I will be able to pick up another mpg or so and get rid of the power robbing inefficient slush box.
j20brett
12-05-2007, 10:14 AM
thats one clean waggy there Pascal. but it sure would look better with a razor up front :D
COLOFIREMAN
12-05-2007, 10:53 AM
Very clean Waggy!! I also thought of the 6BT, but the 4BTA that I'm using just seemed to fit alot better. I can center the weight more by moving the motor back and lower in the frame and have room for the intercooler. There are disadvantages to no intercooler but I think your swap is going to be a great daliy driver/wheeler. :fsj:
GOOD LUCK!!!!!:thumbsup: :thumbsup:
FSJeeper
12-05-2007, 12:17 PM
Very clean Waggy!! I also thought of the 6BT, but the 4BTA that I'm using just seemed to fit alot better. I can center the weight more by moving the motor back and lower in the frame and have room for the intercooler. There are disadvantages to no intercooler but I think your swap is going to be a great daliy driver/wheeler. :fsj:
GOOD LUCK!!!!!:thumbsup: :thumbsup:
I was very, very close to choosing a 4BT. To be honest, it was the noise level that pretty much killed that deal for me. Vibration issues were second. For a weekend truck or something like that it would have been perfect, but not for a biz use vehicle. If it would have been quieter though, there would be no doubt I would have gone 4BT. I think I could have probably got close to 30mpg with it. I have followed your swap over at the 4btswaps page, nice job!
I am lucky in that all of the details of the swap have already been figured out and tried and proven over years of use from my Jeep buddy.
Tanker (MWJT)
12-05-2007, 01:51 PM
Can you post a link to that 4bt build?
FSJeeper
12-05-2007, 02:23 PM
Can you post a link to that 4bt build?
http://4btswaps.com/forum/showthread.php?t=1278
710 Burner
12-06-2007, 07:12 AM
Truth be known.....you are probably doing my planning for me. :thumbsup:
FSJeeper
12-06-2007, 08:01 AM
Talk, talk, talk. Where's a wrench?? :rolleyes:
Most people do not plan to fail, they fail to plan. I am in the planning stage.
Truth be known.....you are probably doing my planning for me. :thumbsup:
Valdez, it is refreshing and rare to someone take a complete turnaround on their position based on one comment from me. It makes me feel so special to be so respected that one comment from me could completely change your behaviour.
Since you have corrected the error of your ways, i.e. jumping into things without thinking them through, it is my pleasure to do your planning for you to help you with your future project.
jeepmj_tj
12-06-2007, 12:21 PM
I just drove my Cummins powered J20 to work today for the first time. Been driving around the house and in a Christmas parade but nothing too far.
Still have a lot of bugs to work out but its finally driving.
You're doing the best thing by trying to plan everything out. I thought I had everything planned but there is always stuff that pops up that can give you headaches.
The J20 springs hold up the weight of the motor nice. Springover I have enough clearance to run at least 37's. Right now I'm only runnning the stock H2 wheels and tires.
FSJeeper
12-06-2007, 12:28 PM
The J20 springs hold up the weight of the motor nice. Springover I have enough clearance to run at least 37's. Right now I'm only runnning the stock H2 wheels and tires.
On my old choptop project with the GM 6.5 engine I ran spring over and J20 280 rated front 7 leaf springs. The springs lost almost all of their arch and were almost flat. I still had way too much lift. I guess my springs were wore out.
How much clearance do you have between the oil pan and the Dana 60?
Have some pics?
jeepmj_tj
12-06-2007, 01:05 PM
On my old choptop project with the GM 6.5 engine I ran spring over and J20 280 rated front 7 leaf springs. The springs lost almost all of their arch and were almost flat. I still had way too much lift. I guess my springs were wore out.
How much clearance do you have between the oil pan and the Dana 60?
Have some pics?
I wish i had a D60, currently its still the factory D44. not really going to 4wheel this truck. I'd like to put a divorced 205 behind my 2wd nv4500, but thats later on as well.
I didnt do a body lift on my truck so my engine is sitting relatively low in the frame. Clearance is ok, but heavy articulation may be a problem. I think a drivers side drop axle would have better clearance. I pushed my engine slightly to the pass. side which made axle clearance a little less, but i need it over slightly to have clearance between the master cylinder and intake horn.
My J20 springs were the 8400 lb rating truck with only 3 long leaves.
it felt nice and spungy without shocks but i put some take off Superduty Rounchos on it and it rides a little stiff feeling now. I plan on putting a set of Superlift standard Hydros on it lateron. As far are ride quality and softness hydros seem to be better on the newer trucks, than the factory gas charged rounchos.
Fiodh. Argus
12-06-2007, 03:16 PM
this is awesome.
710 Burner
12-07-2007, 07:14 AM
We interupt this thread to bring you this important news flash:
I'm a smart@ss. That's probably not going to change.
We now return you to your regularly scheduled thread. ;)
COLOFIREMAN
12-07-2007, 02:17 PM
We interupt this thread to bring you this important news flash:
I'm a smart@ss. That's probably not going to change.
We now return you to your regularly scheduled thread. ;)
:lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol: <-----well we won't hold that against you.
dukeraul84
05-13-2011, 11:20 PM
I had really wanted to do the same thing, but I want the intercooler, and i have a ford 6 speed np271 dana 60/70 for it, so I kinda talked myself out of it. Does anybody think that's feesable?
As far as springs, I was going to run ford coils in the front, and the longest best riding leafs for a truck I could get. Why not just run whatever leafs those heavy duty dodge axles you're running ran?
dukeraul84
05-13-2011, 11:22 PM
I had really wanted to do the same thing, but I want the intercooler, and i have a ford 6 speed np271 dana 60/70 for it, so I kinda talked myself out of it. Does anybody think that's feesable?
As far as springs, I was going to run ford coils in the front, and the longest best riding leafs for a truck I could get. Why not just run whatever leafs those heavy duty dodge axles you're running ran?
Talked myself out of it cause all the swaps I've seen were non inter cooled, and figured the shifter might be in the middle of the backseat to make that happen
seamus
05-14-2011, 04:46 PM
Packaging the intercooler is tough, some have put it ahead of the rad but thats where my fan is going. Its a tight package. Methanol injection can go almost anywhere!
Doesn't the "A" refer to after-cooled?
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