Cummins repower?

[Nightrider]

I thought a fellow on here put a 5.9 Cummins in a 67-72? Does anyone remember the guy? I bought a 92 5.9 with trans and everything, I'm going to put it in my 71 burb{a 1\2 ton}, any one have any suggestions on using big block springs or any problems I might encounter? thanks, I'll be asking for advice on this one!

[special-K]

That`s gonna be cool.I`d think you`ll want to do 1t coils

[Alexis]

how heavy is the motor? compared to a small block? to a big block?

[GMC71k20]

its veedublu - he put the 67-72 body on a dodge frame.

[1969 GMC]

it weighs in the neighborhood of 1100#, i'd definitely ditch the stock suspension.

[4x4Poet]

I don't have much specific info, but I'm considering this swap, so I'd like to ramble...

A customizing shop local to me puts CTDs in 67-72s, as well as most any other full size truck. They just threw a CTD in a '60s F#$d and man-o-man was that conversion clean. I talked to the owner about putting a CTD in my 71 K20. He said no problem, he's done them before. He ran down some of his shop's methods and concerns. I can only relate K10/20 app info:

1. They use the Dodge CTD motor mounts. They remove the K20 crossmember and weld in plate to bolt on fab'd motor mount brackets.

2. They use the Dodge CTD pickup radiator to match hose junctures and then add rad support bracketry to mount the rad. They make a custom shroud for the rad. The shroud they made for the F#$d looked like it belonged.

3. The engine weighs about 300 lbs more than a BB. The owner says the 3/4 ton D44 can handle the weight. Need 3-leaf front springs (or custom) to handle the weight. I have 3-leaf fronts already. I was surprised that he said a 71 K20 frame can handle the CTD weight & torque.

4. Manual trans highly recommended for behind CTD. They install an NV4500. I would want an NV5600 now that an adapter is also available for mating an NV5600 to an NP205. I haven't seen the adapter to know if K20s can use the stock crossmember.

5. Eaton axle can handle CTD torque, though smoker mods can put the axle strength in question.

6. Intercooler complicates things on a 67-72, especially if A/C equipped. One must cut large holes (6-8") in rad support to pass intercooler hoses thru while avoiding PS, A/C compressor, battery tray, etc.. One option is to use a 91 or earlier CTD that did not use an intercooler. (I might be off a year on that) Less power, but far easier install. Installing an intercooler is not impossible, just more complicated.

7. One of the easiest issues to resolve is engine noise penetration of the cab interior. Use Dynamat Hoodliner on hood and firewall, add soundproofing under floormat/carpet, Dynamat behind door panels & maybe inside of doorskins, soundproof kickpanels, interior firewall, & A/C or heater box. More expensive options abound for damping the sound at the CTD itself. A couple companies make bolt-on products that reduce noise transmission at the engine. One must budget for soundproofing if one wants to hear onesself talk while driving.

I've told the owner that he's in competition with a tall-deck truck, Ramjet-equipped 427 with cast headers and spintech mufflers.

427: Do-it-myself install, great torque, poor mileage, quiet.
CTD: Shop install, great torque, good mileage, noisy.

Addressing just the major differences, if I want quiet while accepting poor mileage I'll go 427. If I want good mileage while accepting diesel noise I'll go CTD. Towing is a factor as is engine longevity. And I like to listen to stereo while saving fuel costs, so it's a tough choice.

I'm out!
(Let's see luv2xclr8 top this talking it up!)

[687980chevy]

I know a guy who put a 4 cylinder cummins in his 1/2 ton. It was out of a Frito-Lay step van. It came with a sm465 4speed. I have heard the 4cyl. is the same engine minus 2 cylinders.This might be a option for a half ton. Saw a engine on eBay awhile back with a turbo 350 trans also from a Frito-Lay truck.

[687980chevy]

I went to eBay and there one was!


http://cgi.ebay.com/ebaymotors/ws/eB...939045227&rd=1

[687980chevy]

Picture

[Tx Firefighter]

That's a 4bt Cummins in the pictures. Andy (Longhorn Man) is the expert on them. He works on them daily.

The 92 model Cummins shouldn't have an intercooler. The pump and such should be calibrated to be happy wihtout the intercooler, so the install would be easier.

I have three Dodge Cummins trucks right now, a 94 dually 4x4, a 2002 HO 6 speed, and a 2003 Ho 6 speed. I love em, can't get enough of that torque.

[Nightrider]

Well if i cant use the i\2 ton front end,could I just pirate a 3\4 ton front assembly?Or would it still need more to handle the weight? the motor trans has about 100k on it, with all the miles I drive it seems to be a good choice. Could I use the front end off a newer truck?

[Tx Firefighter]

Originally Posted by Nightrider

Well if i cant use the i\2 ton front end,could I just pirate a 3\4 ton front assembly?Or would it still need more to handle the weight? the motor trans has about 100k on it, with all the miles I drive it seems to be a good choice. Could I use the front end off a newer truck?

You could use 1 ton coil springs if you needed the extra umph to hold the mighty Cummins up.

Personally, I'd likely swap the truck to at least 3/4 ton front suspension like ball joints, spindles and brakes. That Cummins is heavy and those 1/2 ton underpinnings are kind of light duty.

[HOTFUN]

I had researched this quite extensively several years ago for converting my 72 GMC K20. It was far easier to use a running 90 - 93 Cummins Ram and roll the body off and swap the 72 cab and body onto the Dodge frame. I pretty much concluded the intercooler and the factory air condensor would not fit the area in front of the rad support. I then weighed the cost of building such a venture versus just buying a regular cab late model Cummins Dodge with all the creature comforts. Then discount the fact I still have a $5k original truck and I don't think you can build one unless you are an ecentric 72 enthusiast. My newest purchase is a 2000 Dodge reg cab 3/4 and it has all the toys and if something would fail when I am 1200 miles from home, I'm sure it can be fixed just about anywhere in no time. Now if a person can just keep the front end solid under one of these Dodges as they to have plenty of problems too.
Mark

[special-K]

Like TexFF said,I would go to the 3/4t(strong enough)or 1t{better)suspension components.It`s simple enough.Definately use new 1t coils.DO IT!Over on TheDieselPage a guy(Brittanic)has installed a 6BT in a CUCV truck.He would be very helpful(&willing)on the Dodge to GM stuff.I have lots of GM diesel stuff and plan to swap-in a 6.5TD to one of my`72.I totalled my`95 in October.It had a 300hpPeninsularMarine6.5 w/10,000mi.This will basically"bolt-up".I really like the ide of a Cummins swap.

[special-K]

Just was over at TheDieselPage checkin`for more info.A guy named DieselDog has just completed this swap(in a 90 something GM)and is down to working out the bugs...pinched fuel-line,oil-pressure switch hook-up,etc.I think as far as space goes,it will be easier in an earlier truck.