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Discussion Starter #1
So, ive been a member for a while, but mostly just lurking around and absorbing some of the info on the site.

i decided to share what i've done so far to my 1972 K20.

rough sketch of the initial plan.

6bt and manual trans swap.

restore the rest of the truck and modify as necessary. or as i saw fit. sometimes the line between necessary and my imagination get pretty foggy.

Anyhow, the swap is a little more involved than that, but ill let the pictures explain that.

I was given this truck by my grandmother, as my grandfather asked her to do after he died. that was in 1997. i was 13 then. i had high hopes of making this truck into a mudracer that i could still drive to HS and be a total ladykiller with. hahaha.

i intalled a huge all spring skyjacker lift, later model one ton axles and bought some big old MT tires. then i was strait out of money. The ol' man had installed a 5.7 buick diesel and a np425 4 speed. so the idea for the current phase of the project has a little to do with making the truck grandpa wanted. mostly its because i wanted it but the idea was all grandpa.

so, it was a gutless turd to say the least, but i drove it for a while trying to scrape some cash together to build a decent BBC for it. eventually just before i took off for college, i yanked the 5.7 and prepped to build a 454. i got so far as sending the order for my internals to Jegs with the check. they biffed the order somehow and never sent the parts or cashed the check. then i was at college and the poor truck got stuck in the most convenient spot at the time. eventually it landed in my dads barnyard. there it sat for 8 years or so. i robbed the tires when i was building my M715.

on labor day weekend of 2011, i decided it was time to collect my truck and start doing something with it. i bought a nice new trailer and hitched up the wagons. by this time i live in SW colorado, so it was a little over 1100 mile trek.

i removed the big lift and installed a more civil, less high school 4" before it went on the trailer.

this is the day before the haul back to CO.


installed it in the garage at home and got to work. slowly

got the frame blasted. somewhere in here, i horse traded with a buddy to have my garage wired for the air comp and welder in trade for some sub frame connectors in his dart.
 

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Discussion Starter #4
the rear of the frame was pretty ugly. lots of pitting from the salted roads and 40 years of winter. the truck actually only saw about 20 years of service before it was parked.

so i built a new section out of 3"x4"x.1875" tube. drilled and sleeved for a bumper at some point
 

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Discussion Starter #6
All the while i had been patiently searching for my donor powertrain. i had been entertaining the idea of doing a Duramax as well, but i found the 6bt first. and considerably cheaper.

i didnt get any better shots of this wretched heap, but the engine ran well. it had 166xxx on the clock. it had been wrecked pretty hard, but mostly the front axle was took the hit. t-case was cracked from the axle pushing back as well. it had an re47.



pulled it apart, in one of many such events that cause my quiet residential neighbors to look at me funny

put the engine in the garage and picked some other parts off the scab of a dodge. then sent it to the crusher



had to hurry up and get the wheels on the chevy again so i could play with the engine mounting.

the rear just needed some welding and it was good



i machined down some 2"x.250" DOM to work in the OEM hole in the frame for the front shackle mount. welded it all in, reinstalled the axle and sat the cab back on.



 

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Discussion Starter #8
some test fitting.



some engine mounts



some wild firewall butchery. this isnt needed for the engine to fit. i really just wanted to center the weight as far back and as low as possible. the engine is lower than most swaps as well, but that made moving it back more necessary to provide adequate clearance at the pan. and the lower and more centered the COG in any vehicle the better it performs and handles, in any condition.



had to do some clearance work on the frame for the vacuum and ps pumps. another step usually not required



Up to this point i was a little mixed up on what i was doing for a t-case. i want this truck to be easy to shop for, easy to drive and comfortable. after some chatting with friends i decided the 241 was a better choice. they dont have the high torque input case failure issue that 205s do(not that i'm building a pulling truck...) and they are easy shift on the fly and quiet. i know all those things are easy to accomplish with 205s. i've built enough of them to know what it takes to make them shift easy and run quiet. i was more having trouble finding a dodge 205, and i was worried about the exhaust routing. i stumbled on this to solve my headache. the guy just wanted to trade strait up for a GM 60 and mine was in pretty much the same shape as his.

 

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Discussion Starter #9
It is a 78-9 ford dana 60. HP and the same spring spacing as gm

after that happened, i got the engine hard mounted



clearance on the axle was looking great



i had decided to build and run the auto, since i had it. autos can be fun.

so i chased down a deal on the 241 dld and a dana 80 for the rear. the 70 out of my donor was less beef than i wanted and it was 4.10 geared. i was looking for 3.54 and this fit the bill



the 80 was in really nice shape, but needed brakes from the backing plates out. i did bearings and stole the backing plates off the 70. i ended up stealing a hub from the 70 to as one of the hubs on the 80 looked like the bearing race has slipped. it wasnt full on spun but i figured if i had the spares i may as well swap to one that looked right.

cleaned and painted too



continued on replacing crossmembers and boxing the rear portion of the frame

 

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Discussion Starter #10
At some point i found this rebuilt (stock rebuild not performance) 47rh on CL and scooted up the mountain to get it.



and i built a trans crossmember/mount



did some more work on the back of the frame



installed a B&W flip over ball on some crossmembers i made of 2"x4"x.250" rec tube.



built this fancy pants front crossemember



and installed it

 

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Discussion Starter #11
my first plan was to use the stock GM 4 row radiator. i know 6bs dont generate a lot of heat, but i got a little twitterpated and decided to make the dodge radiator and I/C fit. my justification was that if it was designed to work for the engine by detroit, why mess with that. and its a lot easier to order a part for a truck that is only a decade old as opposed to one that is closer to half a century old.

i cut, chopped and whittled until i had space. not much was left of the core support, so i beefed it back up with some 2 inch square and some 1.5 inch square as well as a little bit of sheet metal for the rad and I/C to sit on. the end result was that the mounting is the same as a second gen and used all the oem bushing for that truck.



this is the step piece i welded in the bottom of the core support. it steps to provide the correct location for the mount bushings on the two different cores. it also help to add rigidity back to the core support. in the end the system worked really well and was less prone to flex than the stock set up.





then i decided to get funky with the brakes. i hate the idea of crappy brakes. so i scooped these 2005 3rd gen dodge brakes up at the JY. the hydroboost is 2nd gen dodge and plan number one.



the hubs got machined a little on the flange, the abutment bracket was waterjetted and it all bolted back together



bigger brakes and no more pressed on rotors!

 

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Discussion Starter #13
Nice work, I love the story behind the truck.:)
thanks!

I have to give you the credit for causing all the trouble with the core support. i read through your blazer swap thread and that tipped the scale for me. that was an excellent build
 

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Discussion Starter #14
That last pic does not really show how the abutment was mounted to the knuckle. In restrospect, i wish i had done a touch more looking before i went this route. the '10+ dodges use an abutment and mount that is symetrical and would have been a bit less of a pain to design around. the caliper and rotor are pretty much the same, so all i really lost there was my time.

this is the backside where it all mounts. the waterjetted bracket, that is bolted on by the spindle has a few pieces of DOM welded in the holes on the flange. they space the piece that the caliper abutment bolts to with the m16 bolts.



after that, i decided a fuel tank was in order. while i have no issues with in cab tanks, i was hoping to gain a few inches of room for the seats in the cab and a place for some other stuff. speakers, electronics etc. not to mention the stock tank on these trucks is about 19-20 gallons of usable fuel before you start sucking air. i wanted a little more range. i think i calculated it to the area of 600 miles if i can squeeze 36 gallons of usable space out of this box, and get 18 mpg. hopefully i can break the 20 mpg mark with sensible driving, but i didnt want to set myself up for disappointment. the tank volume is closer to 40 gallons, but i dont like to figure it to absolute empty.



i wanted the draw from the tank up higher, for aesthetics mostly, and for a little easier fuel line routing. so i welded these steel fittings in. they are just NPT tp JIC adapter fittings from the local hydraulic supply.



then i bent and welded some stainless tube into the tank. using 309l wire i glued the fitting to the draw tube and stitched it to the tank bottom as well, so it wont vibrate and fall off.



added a couple of floor to ceiling baffles to keep the slosh monster at bay. these do not continue all the way to the bottom "sump" area of the tank.



i made some straps and hung it in the frame. i still need to decide how i am going to go about the filler, so this will be revisited. at that time i will probably use all the material cost savings of not making a stainless tank on a tank coating. wish i would have looked into that then...



 

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Discussion Starter #15
So, depending on my inability to focus on one thing, i skip around a bit, as you may notice. in the middle of the fuel tank thing, i started thinking about an electricity tank. batteries are ugly and cumbersome, not to mention heavy. i like to balance the weight as much as possible so i wanted the batteries out of the engine compartment. this was a quick and easy part. i havent made the hold down yet, since i may end up with some other stuff around these.



oh wait, i got distracted by that big ugly hole in the firewall



Ok, thats fixed. back to the batteries.

this isnt even linear to how it happened, i am making more sense of the order of operations by posting the pictures in a less confused order than what i actually did the work... i have focus problems...



oh whoops, remember that core support? well keen eyes would have noticed that i never mounted the top of the I/C. i guess now is as good a time as any



earlier i said that the dodge HB was plan one. i got the unit from a cool old guy i work with. he had it as a replacement for his 2nd gen, then sold the truck. brought it in to work one day and said "all yours" unfortunately it was 35 feet to long. i swear with the booster and the MC from the dodge hung off the firewall on the dodge bracket, it tickled the core support. the GM style HB has a slightly shorter overall length on the body of the booster itself, so i snagged this one off a safari van at the JY and picked up a new MC for a 95 K3500. the MC was chosen for its bore, and the fact that it matched the HB unit a far as the pushrod goes. you can see how it is close to the stock intake horn. it still didnt fit, but required much less pain and suffering than the dodge unit.



i made the bracket to bolt it to the 72 firewall. later, i will address attaching it to the brake pedal.
 

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Discussion Starter #16
the flat cheesball bracket in the previous pic was a quick and dirty mock up done on a sunday in the garage. i made a slightly more professional looking one at some point



cleared everything on the P7100 with no issues



when i boxed the front areas of the frame, i knew this was waiting for me someday. i picked up a little piece of .750"x.156" wall DOM and sleeved the steering mount area.



and also since the engine was out again, for whatever reason, i finished on the patchwork firewall

I'm not a sheet metal guy, so this is as good as it gets from me. i wish it was "HOLY COW" nice, but whatever.



here is the reason i yanked the engine. i had some Iowa rust issues to address.





this was pretty much the same side to side. rockers, supports and cab corners. this was my first time on rust repair. i know there is a bunch of guys better than me when it comes to this stuff, but i was pretty happy with my efforts. the paint guy has yet to gripe to much(or actually do anything to the truck...)
 

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Discussion Starter #17
At some point in here, i snagged a couple of decent doors and a really good tailgate from CL. But that isnt fun to look at, so... onward

this is the end result on the firewall. again, i wish it was more BA, but its all going to be hidden by that 6BTA awesomeness.



there was a little more rust repair in the windshield frame and some kick panel repair as well. i also fitted the doors to make sure the rockers came close. first time in over a year that it looks sort of truckish again. the bed was a CL pick up at some point as well. i think it will be replaced by new bedsides and maybe a new floor, but i havent pulled the trigger on that yet



while i was doing sheet metal stuff, i cut and patched the firewall to accommodate the difference in factory a/c cabs and non a/c cabs. i also cut the dash for a/c vents and bit the bullet and cut the dash for a stereo.

so, after all that, i found this add on CL and my first plan for the drivetrain was reborn



later style 2nd gen NV4500. needs a rebuild, but thats not a big deal. i think i paid 300$ for whats in the pic.

you may notice something of importance laying on the floor next to the trans. i had been worrying the idea of airbag rear suspension around in my head from the very start. i had been pretty good about killing the idea, telling myself to get the truck driveable before i got silly with stuff. as they say, idle hands are the work of the devil...

a long sunday at the computer, preceded by a long saturday with the angle finder and tape measure.







and a monster was born
 

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Discussion Starter #18
For whatever reason, i didnt have much going on with the truck, so i decided to take the 4 link brackets to the next level. spent a few nights after work, cutting, bending and welding. the little pieces welded on are basically weld washers, intended to spread the load of the bolt over a greater area, reducing the chance of the holes wallowing out over time. for what this truck is going to do, it was more for the flash bang look of it than real necessity.







then it was time to consider the mounting



oh wait, i havent test fit that NV4500 yet. hope the BH fits where the 47re was before...

its close, but it should work. a couple of the bolts are a pain, but i hope to not worry about it much after its in.



 

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Discussion Starter #19
as part of the fun, i had to cut and re attach the rear cab mount. in the end i have changed a few things about how that will work, but it should be great. now the bolts will come in from the top and use a heavy spring instead of a second bushing to accommodate chassis wiggle.



the big brown truck delivered, and i am back on the suspension



air bag size large... check

setting the pinion angle. i used some thin wall square tube to make some mock up links.



had to make this panhard mount a little silly to clear everything, but its got the beef.



waiting on parts to get delivered, so i decided to be productive. new trans mount for the 4500

 

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Now that is done, and my link stuff got backordered, what can i do to make my life more problematic...

i suppose a filter relocation is a decent idea. i hate fishing my hand up there to get that filter...



I bet i could find a filter head with enough searching, but whats that, a stub of the perfect sized aluminum round i need. heck why not



version one, complete



i am no where near needing this stuff, so it seems natural that it would show up now instead of my link stuff. this is the regear and master kit for the front 60. i didnt realize that HP gears where double the cost of LP. oooff.



and finally link ends, tubing and weld bungs all finally showed.



2"x.250" dom, 1.25" rod ends on the axle end and big ol ballistic fab poly bushings on the frame end
 
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