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I would recommend not using a water to air cooler setup. They are a big restriction in the intake and cool very little if at all. Adding another pump, extra radiator, expansion tank and all that plumbing is a hideous mess under any hood.

Air-Air is the way to fly.

If you can't do air-air (looks like there's a ton of room for it to me) then don't intercool it. Non-intercooled you will find it's limitations and just live with them. It's better than sinking all that work and money into air/water to have something that's worse in the end (Been there, done that).
 

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Funny, our 6BT seemed to pull the GV OD that I just had installed right nicely. The GV guy that I talked to didn't want me compounding the OD's, said it was too hard on the OD unit. The way he phrased things made me think he may not have really known of what he was speaking about either.

That said, if you're in farm country like it looks to be I'd go looking thru your friendly neighbor's junk vehicles to see if any of them had an aux trans. My grandad found one in just such a place on a farm a couple miles from his place. The farmer that owned it didn't think it was worth much since all of the rest of that truck was pretty used up. Sure perked up that '62 F-600 and let that little 292 Y-Block do some work. Sure wish I had that truck now.....
 

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Discussion Starter · #23 ·
Wonder if those hubs could be moved to a modern type axle?
I know it has Dayton wheels, there are lots of box trucks around with Dayton’s, getting hydraulic brakes wold be less common.

Ed in CO
Ive been wondering about swapping the hubs to a different axle but Ive not found any good info to actually see if it could happen. Weird thing is that the center section of this diff is extremely similar to the SQHD tractor axles. Same amount of stud holes though they are of a larger size, same pumpkin design and build. Only stipulation would be if the axle shafts would work or not I think.
 

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Discussion Starter · #24 ·
Funny, our 6BT seemed to pull the GV OD that I just had installed right nicely. The GV guy that I talked to didn't want me compounding the OD's, said it was too hard on the OD unit. The way he phrased things made me think he may not have really known of what he was speaking about either.

That said, if you're in farm country like it looks to be I'd go looking thru your friendly neighbor's junk vehicles to see if any of them had an aux trans. My grandad found one in just such a place on a farm a couple miles from his place. The farmer that owned it didn't think it was worth much since all of the rest of that truck was pretty used up. Sure perked up that '62 F-600 and let that little 292 Y-Block do some work. Sure wish I had that truck now.....
I got the same feeling from the guy, almost like he was reading from a script or something. I honestly dont see how the OD would be under any more stress if you were running double over... it just doesnt make any sense as the GV has no idea what gear you happen to be in nor should it care. I could see over speeding it being an issue though, thats why I wanted to talk to the guy about it.

as for the brownie Ill have to do some digging for sure, not allot in the way of wrecking yards around here to dig through, atleast none that are filled with big trucks.
 

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Discussion Starter · #25 ·
I would recommend not using a water to air cooler setup. They are a big restriction in the intake and cool very little if at all. Adding another pump, extra radiator, expansion tank and all that plumbing is a hideous mess under any hood.

Air-Air is the way to fly.

If you can't do air-air (looks like there's a ton of room for it to me) then don't intercool it. Non-intercooled you will find it's limitations and just live with them. It's better than sinking all that work and money into air/water to have something that's worse in the end (Been there, done that).
I thought about just leaving it non-intercooled but i wasnt sure if it would really enjoy life like that. I wanted to turn the screw up, make like... 250 horse or so just to move this thing and the trailer down the road at a reasonable clip.
 

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Funny, our 6BT seemed to pull the GV OD that I just had installed right nicely. The GV guy that I talked to didn't want me compounding the OD's, said it was too hard on the OD unit. The way he phrased things made me think he may not have really known of what he was speaking about either.

That said, if you're in farm country like it looks to be I'd go looking thru your friendly neighbor's junk vehicles to see if any of them had an aux trans. My grandad found one in just such a place on a farm a couple miles from his place. The farmer that owned it didn't think it was worth much since all of the rest of that truck was pretty used up. Sure perked up that '62 F-600 and let that little 292 Y-Block do some work. Sure wish I had that truck now.....
Gearvendors is the wet clutch overdrive from a 1960's Volvo car. It was designed for 2500 lbs and 100 HP. They are OK in light vehicles on level ground, but fail pretty fast if you work one.
 

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I thought about just leaving it non-intercooled but i wasnt sure if it would really enjoy life like that. I wanted to turn the screw up, make like... 250 horse or so just to move this thing and the trailer down the road at a reasonable clip.
Well, you're darn sure not going to get there with that water to air thing. They were made for 150 HP and that's about all they will push.

Have you driven a non-IC first gen Dodge? Stock, the non-IC first gens have way more gusto than the intercooled trucks do. They de-tuned the pumps when they went intercooled to make less power. I have grossed around the 20K lb mark with several stock 1st gens and the non-IC trucks will pull it faster. This is with a stickshift of coarse. You can't tell with an auto. They are horrible.

This could be real cool when it's done, but it could also be a complete disaster. Putting a Cummins in something doesn't make it awesome. It's all about the execution and the details. The only way you get those things right is with research and careful planning.

Because this is such a big project, you are going to have tons of custom bits and nothing is going to fit the way you think it will I would highly recommend simply not concerning yourself with an intercooler at this time and do the project incrementally.

I would try to get the rear axle sorted first. That is a road block you cannot get around. The truck is useless with the stock rear axle. Not driveable, not fun and pointless. If you do all the work to install the engine and trans and drive it with a top speed of 40 MPH you'll be pretty disheartened with the result. Rear axle first gets that big potential project staller out of the way.

Myself, I would use a Dodge or Ford ZF transmission if it were me. That aside, your best bet for medium duty truck clutch and all that is to find the complete 6 speed Eaton and all mating components from a 90's F series or Freightliner FL60/70. Then you know what you've got and know the parts work together. You should be able to find the entire setup, trans and all, for under $500. Less than the flywheel and clutch will cost you for the setup you have now.

Once you have it all driving non-intercooled and work the bugs out, take a break, enjoy using it a bit, and contemplate what an air-air intercooler would look like.
 

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Most any thing over 160 HP will need an intercooler. I'd disagree with Snuggletough about the water/air aftercoolers. They are found on many large diesel truck engines, high performance sports cars, and all the new Ford pickup diesels. They are more efficient at removing heat that air to air. Their main drawback has always been cost. Cummins used a common radiator for engine and air cooling but the good systems have a separate radiator and circulating pump. They are less cluttered that air to air because you don't have all that large air piping going all over the place. One crossover tube going from the turbo to the aftercooler and 2 water hoses.
 

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The Cummins ones are made from 410 stainless steel (A very poor grade of stainless, same as most OE exhaust systems use)

Stainless steel is a very poor heat conductor.

We have tested them intercooled VS non-IC and non-IC beats it hands down just on the restriction to airflow alone.
 

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Curious what are the ones made of used on the big trucks or the Ford pickups. Also, which one of the Cummins units did you test. They have several different models for both 4bt and 6bt. So you're telling me that pushing 300+ deg air without an aftercooler produced more power than with it. How much air flow reduction did you register?
 

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On a Big Cam or a Ford 6.7 they are aluminum.

We used a w/a 4BT in a swap that would not perform as expected. It was a fresh engine build and the intercooler was professionally cleaned like new. We pulled the cooler and non-IC had an immediate huge improvement. We went a/a and it worked great.

Several years later we got a 6BT for a project that came from a vandalized Kobelco processor. It had the w/a setup on it. We did a full engine build and put it on our DT1000 Go Power engine dyno that was new to us at the time. We weren't planning to keep the W/A setup, but wanted to see if our 4BT experience was a fluke or not. This was around 2008 so it's been awhile, but as I recall EGT's were getting uncomfortable just past 200HP. Swapping to the standard 2nd gen Dodge IC and piping we use on the dyno without much air moving over it the same engine was very happy maxing out our dyno over 375HP and 1000 lb/ft.

IMO, the B series Cummins W/A setup was made as a sales gimmick to upsell customers on an intercooler, but it wasn't very effective in use. The way the air flows through the W/A setups is not smooth. I think that is why they are worse performing than non-ic.
 

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Gearvendors is the wet clutch overdrive from a 1960's Volvo car. It was designed for 2500 lbs and 100 HP. They are OK in light vehicles on level ground, but fail pretty fast if you work one.
They "rate" them for much higher loadings than that (by way of their applications listing if nothing else). FWIW no Volvo that I've ever worked on was that light. They're the old school Safety Nut's car of choice for a good reason, and that doesn't come light.

That said, of course I'm not going to try to pull steep hills in compound OD. The GV OD worked well on just such a grade a couple weekends ago. Allowed me to split the difference btwn the 47RH's OD (too tall to pull on that hill) and Direct (slow enough to require the hazard flashers). To me the serious down-side to a GV is where they put it hanging way back there off the backside of the transfer case. I need to build a supporting cross-member for it.

Years ago a co-worker at wilwood had a Ford SD gasser with a Kenn-Bell supercharger on it. His intercooler was a w/a system that used a PSD's a/a cooler core as it's radiator (since it bolted in like stock). Claimed it worked better than plumbing it a/a, but I've always suspected that he was too lazy to do the a/a plumbing and that it worked only because the cooling core was so huge. A very large percentage of the total system's coolant capacity was contained in the cooler.
 

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Discussion Starter · #33 ·
Got the new manifold mounted and torqued down. Also got the turbo bolted on and plumed in correctly. I modified the original oil drain for the turbo to make it work with a longer chunk of hose. Turns out with some heat you can just heat up the flange and spin it on the pipe a bit to get the correct orientation. Was able to keep the stock oil feed line by adding in a little brass 90 from fleet farm so there was money saved there.

On the axle front Ive been thinking about swapping out both front and rear now. Finding a suitable dayton rear is becoming a bit of a pain and most of them Id have a hard time finding parts for. Its now ocurred to me to look into Isuzu NPR axles being that they use the same old school bud style rim as the old rigs did, 6 lug with somewhere around an 8.75 bolt pattern. Ive got access to a few of them so maybe I can find something with a decent gear ratio and go from there...

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Now, if you had an HX35W turbo on there it would look just like the engines used in the Ford medium duty trucks except for the aftecooler. One thing in the discussion on the 6bt aftercooler that wasn't mentioned is which one was used. There are 3 designs, one of which is a marine version we wouldn't consider. The first style shown below is part 3919806 which has changed part numbers 5 times. Newest number is 5262611. You note that this one has one smaller air inlet.
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The second style is part 5262612 which has 3 air inlets and should flow much better. This one is designed like the 2nd style used on the 4bt engines. Both cost about the same money but the newer style will be more expensive due to its crossover pipe.
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