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'94 Cummins Powered '49 Willys Pickup

36K views 98 replies 17 participants last post by  Redrider2911 
#1 ·
Hello all. I am in the process of droppimg a 12 valve into a Willys Pickup. I'll post up some pictures later. For now I have a few questions that have been floating around in the back of my mind as I work on the suspension and stuff for the rest of the truck.

Of course this engine is longer than the stock flat head 6. So I pushed the engine back just enough to leave room for a 3 core radiator bolted to the back of the stock grill. I will be making a custom firewall, floor, and trans tunnel.

I have ran into a few problems/questions.

This leaves the hot side of the turbo barely 3" from where the firewall will be. Is it as simple as I would expect to flip the exhaust manifold to gain a couple inches of clearance?

The nose of these jeeps is pretty narrow, it looks like I will barely be able to fit the stock Dodge AC condenser in front of the radiator. What should I do for an intercooler? How small can I go before I lose efficiency? What about water/air intercoolers?


I would appreciate any help and support I can get for this project. I'm not in anyway new to custom fab and solving problems. Just trying to see if anyone more familiar with custom Cummins swaps would have some good insight.

Thank you,
Kris
 
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#2 ·
Here's how the truck sits now. 32" tires (will be 35s when finished), front and rear axles from the donor Ram 2500, 3 link front and 4 link rear with bags all around, custom 2x4x.1875 tube frame, 9" stretched cab with bucket seats, going to be a custom 7'6" bed, gooseneck hitch, and bumper pull hitch.









 
#3 ·
Thats going to be one cool truck! Unfortunately I can't help much on you questions so hopefully someone with more experience in that department will chime in.

I know there is another guy on here who did a willys conversion - maybe search for his thread because I am sure some of the answers to your questions are in there.
 
#4 ·
Got to do some work on this thing. The wife was complaining that it was too high to get into, so I let all the air out of the bags to show her it could get lower. Lol



 
#5 ·
Alright. Votes on leaving the bed this length or bobbing a few inches off. Keep in mind ride height will be about 3-4" higher, tires will be 35"+ instead of the current 32s, Also remember right now there is no fenders, stake pockets, bed side panels, and side steps that will help break up the length.

The bed currently measures 7'6"
 
#6 ·
This truck was cool, And then you put a cummins in it..... And made it obber cool lol As far as innercooler you can go aftermarket and get a lot smaller then factory dodge or others and still keep great flow, also ice water coolers are quite tiny and able to run even beside the engine. To me it depends on what your going to do with the truck... If its gonna be a high horse power build then then you want all the air you can get, if its gonna have some upgrades to run well 3 or 350 horse you can slide by with just about anything. Same with the bed IMO. If its a street truck with some mild wheeling then leave it long be able to throw something in the back of it. If your gonna get into the sh!t with it, Its worth cutting it to the shackles. ether way its gonna be a cool truck, just thought ide throw up my two cents... DOnt be afraid to do lots of searching on here thats what its for, and ask lots of questions. There are some smart talented folks on here that are always happy to help.
 
#7 ·
Been slowly working on this thing. Had it sitting on 32s during a lot of the mock up. Grabbed the 37s off the Cherokee the other day to get some ideas. Thinking Ill end up running 35s.

Hoping to have it done here in a couple more months.







Floor was rotted so I redid the whole thing since I had to do the firewall anyway



 
#9 ·
Beautiful floor. What equipment are you using just a standard box and pan?
 
#13 ·
Thanks for the compliments guys! Helps keep me motivated to work on the long list of stuff I still have to do.



I have access to a full shop (my job). We have a CNC High Definition Plasma cutter, a hydraulic press brake, a mechanical press brake, and a full CNC hydraulic press brake. The only thing we don't have that would actually help making these parts quicker, is a box brake.

When you do custom work you have to redo the math that the factory engineers did, there are tables/conversion numbers for intercooler size, and radiator size. Alot of people run smaller, and don't tow as much... nice truck by the way!
I think Im going to go water/air. Get as big of a heat exchanger as I can fit behind the grill, before the radiator. Hopefully it wont heat soak when pulling a load.
 
#14 ·
I got the 36 gallon fuel cell all buttoned up the other day and started it just to make sure there was no leaks in the fuel system. Im working on brake lines now. Then I think I will tackle shock mounts.

 
#15 ·
In some of my free time I have been reading through BigBlue's 95 Junker thread. I used his transmission build as the outline to order my parts from; I was excited to stumble across his Junker build thread FULL of awesome cheap and applicable tech.
 
#16 ·
I just realized there were more pictures I hadn't posted.

This is what I came up with for the gauge cluster so far.



Transmission mount I finished up the other day.

 
#18 ·
Custom turbo manifold out of sheet metal? Sure! Why not?


 
#21 ·
Ordered all the transmission parts today. Pieced together rebuild kit following Big Blue's clutch pack upgrades, RevMax Stage 3 Torque Converter, Transgo TFOD-Diesel Shift Kit, and Goerend Billet apply lever, strut, and anchor. This thing should be driveable in 2 weeks time.
 
#23 ·
Thanks man. Excited that it will hopefully be driving real soon.

Yes sir.
 
#24 ·
Took care of the killer dowel pin today and advanced the pump timing from 13.5 to 17.5 while I was in there.
 
#26 ·
Thanks. Hopefully it will work alright. Lol the only thing that I think I should've done www maybe add a partial divider between 2nd and 3rd cylinder to direct flow out to the turbo flange. But I guess the turbo really should be driven by the pressure differential pre and post turbo correct? Flow diversion shouldn't be that much of an issue?

I think I will be mounting an external wastegate between cylinder 3 and 4.
 
#27 ·
I dunno. I've flunked just about every science class I've taken, and fluid dynamics or physics ain't my cup of tea.:hehe:

I like that you bent it on three sides instead of trying to use plates on all four sides. I initially thought that's what you were doing and I went "uh oh" in my head. Bending to form and then boxing in on the flange side, definitely the way to do it.
 
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