71 K5 with a Cummins

[CUCV2]

Still getting the parts together for the steering. Ordered up a Borgeson shaft for a 93 Dodge because I am using the column from it and thought I might be able to use the Dodge steering box as well. Also, have a PSC steering box set up for hydro assist as a possible option. Got the Borgenson shaft and tried it on the PSC box. Apparently, Dodge uses a 30 spline shaft and Chevy uses a 36 spline shaft to attach at the steering box. So, I was just going to use the Dodge steering box but it was a rusted mess and set up for the push pull type of steering. I have a crossover set up ready to go in and the PSC box is set up for crossover. Ughh. I called up the guys at PSC to see if they could help me out. And what I thought might be an issue really wasn't. They are going to send out a 36 spline end to fit on the Dodge shaft. They were even good as far as sending the 30 spline unit back for credit. Thanks PSC . When that part gets here, I should be able to get the steering put together. In the meantime, I will get some power steering hoses made up to plumb the Dodge power steering pump to the Chevy steering box.

Also, checked out some Dakota Digital Dashes. They are pretty sweet.
http://www.dakotadigital.com/index....tegory_id=662/home_id=-1/mode=prod/prd776.htm
The classic dash units are nice too.
http://www.classicdash.com/shopping...ack-6-Gauge-Panel-with-Auto-Meter-Gauges.html

 

[CUCV2]

I thought having power steering hoses made up would be easy. I even brought the power steering box and the Dodge lines, so they could see the ends. The local auto parts store, that supposedly specialized in making power steering lines, looked at it like it was a Rubix Cube. The steering box fittings, of all things, had them baffled. It is a PSC box. So, I thought that maybe PSC uses some special fittings. So, I went home and called PSC and even sent them pics of what I was working with. They told me the size and type of fittings and that it was a standard 72 K5 format. OK, now I knew what I had but still needed to find some lines that would work. This time, I went to my usual auto parts store and found the store manager. He was willing to work with me on it. Turns out a 3/8 brake line had the right fitting for the smaller size. The bigger size was a little more challenging. The manager researched it and would have just ordered a hose for a 71 K5 but they were out of stock. Not a lot of 71 K5s that need power steering hoses replaced up here in the rust belt must be. But he kept at it, thankfully, and found out that a 74 K5 had that same fitting and they did have one of those in stock. So, as it turns out, I ended up using the stock power steering lines for the Dodge. Just put the Chevy fittings on the end of them. Wish I would have had those handy .

Here are some pics of the ORD steering box brace welded in and the lines. Steering box is waiting to get mounted sometime after the frame gets prepped and painted back up.

 

[CUCV2]

Got a garage pass this weekend, fired up the woodstove, and got some painting done. So, now the steering box is on and hooked up. This led to a slew of other issues though.

The first issue was the 93 Dodge replacement shaft (connection from the steering box to the column) from Borgeson was too long to fit in the K5. The new universal joint that they sent out fit great though. I had kept the original Dodge shaft, a 93 Suburban shaft, and what I think was the original shaft out of the K5. The K5 shaft showed the most promise. The rag joint side needed the bolt holes drilled out to the same size as the Dodge column bolts and steering box side of things needed to be shortened.

The second issue was centering the steering wheel (Chevy box to Dodge column). Just turned the steering wheel from lock to lock counting the turns, found halfway, adjusted the wheel at splines on the steering box, and got a centered steering wheel after the third adjustment.

The third issue was that the steering column angle and the connector shaft were at two different angles causing some slight binding when turning. It was good news as it turned out because the column height was a little high in the dash. Meaning the guage assembly needed more room. Some spacers are in the works to correct this.

The fourth issue was fairly minor. The crossover assembly just needed to be cleaned up and painted.

So, with the steering gear in order, it was time to move into connecting the intercooler. The turbo side was great. The 93 Dodge piping and bends fit as they should. The intake horn side was another story. The intake horn itself comes out at a 90 degree angle right into the master cylinder. After looking through other Cummins build for ideas (love this site). I found Moses 'Burb had a Banks intake horn that 90'd towards the radiator and that other builds with a 2nd gen Cummins have an intake horn that sweeps at a 45 degree angle towards the radiator and down a touch towards the intercooler. There is a local guy who sells Cummins parts that said he would sell the 2nd gen intake horn and piping/bends. Hoping that this will give the necessary clearance. There is a catch though. The first gen intake horn size is 2.5". The 2nd gen intake horn is 3". Found the cure for that here:
http://www.siliconeintakes.com/index.php?cPath=14&osCsid=a4e1d9c517ddef18215e2f8bc81071c1

Time to gather parts and think about what is next. I am thinking brakes, exhaust and then buttoning things up for (at least I hope anyways) a start-up. I still need to plumb some fuel lines but a can of diesel and some rubber hose will suffice for now. I need some motivation .

 

[CUCV2]

One step forward and two steps back. At least that is what it feels like. I purchased a 2nd gen Cummins Intake horn for the intercooler and put it on. That all went ok but I decided to put the master cylinder on to see how that fit. They both fit but with fraction of an inch between them. And the motor is not quite in it's final location. It actually needs to be clocked closer towards the master cylinder. So, the question is, "How do I get the necessary clearance?" Still toying with a couple of ideas like a different intake plate, looking for another intake horn, or a custom intake horn. Enclosed a pic of how tight it is and the steering finished up. Might just start working on the brakes until I can find an intake horn. Ohh, the humanity...

 

[ashman]

bummer man! I'm sure you'll get it figured out though. It might be worth looking at the booster/MC side of things too. Maybe a slightly different style would get you some room too.

 

[CUCV2]

That's a good idea. Not sure where to start on that one though.

I did do some research on custom intakes. It is pretty straight forward. Just a flat plate on top with a 2.5" hole bored through and some mandrel bent piping welded to it would do the trick. After looking at the stock intake, it could help to flow more air as well.

It is kind of funny how progress does not always feel like progress. But really this just got me started on the brakes. I also checked the fit on the down pipe for the exhaust. It has clearance a lot like the intake horn but it may be able to be bent to clear at least...

 

[Greg72]

Build an offset bracket that moves the entire brake pedal assembly and MC into the cab area maybe 1/4"...???

How much extra clearance do you need?


-G

 

[CUCV2]

Build an offset bracket that moves the entire brake pedal assembly and MC into the cab area maybe 1/4"...???

How much extra clearance do you need?


-G

Thanks for the idea. How does that work?

I would need to rotate the engine to know exactly how much but I am going to say it needs about two more inches of clearance. I had a fleeting thought about doing a one or two inch body lift for two reasons. It would give me some needed drive train clearance and allow the rear X member to be installed higher which would tilt the engine forward some. The two combined movements would probably give the right amount of clearance.

The other side to this is that I wanted to actually drop the height of the K5 a few inches. Which is possible. I could use some stock 56s in the rear (with the shackle flip) and do something different with the front. I do need to be 4" higher than stock according to the Cummins Xmember guidelines. It is on a set of stock 52s in front now.

Really just random thoughts at the moments.

 

[Greg72]

Two inches is not what I was expecting to hear.....that's not going to be a simple little "tweak" to resolve.

I'd have to see better photos to understand where the interference is, and what space is still available. The problem with moving the MC is that the whole system is set up with specific motion ratios (pedal length to pivot, pivot to MC actuator, acuator throw length, etc) so you can't just start "extending" parts of the braking system to gain clearance. You either move the entire thing as one large component or you re-design it from scratch.....


-G

 

[bp71k5]

They do sell master cylinders that are smaller or different shapes than the stock one.

 

[mosesburb]

Why not just take the original plenum elbow that points at the master, open up the bolt holes a little and install it pointing forwards?? Maybe the holes would have to be welded up and re-drilled, but it seems easier than all this other stuff.

 

[DEMON44]

Holy hell, don't move the master. Build your own elbow like was mentioned. You obviously have a welder and some fab skills. Cut a 3/4" plate to square, hole saw it to whatever you want. And weld a mandrel elbow clocked however you need.

 

[CUCV2]

They do sell master cylinders that are smaller or different shapes than the stock one.

That is definitely an option worth checking into. Ideally, I would like to modify something that could be an upgrade of some sort though.

Why not just take the original plenum elbow that points at the master, open up the bolt holes a little and install it pointing forwards?? Maybe the holes would have to be welded up and re-drilled, but it seems easier than all this other stuff.

That is a good thought. The difference in bolt hole widths is +/- a 1/4" and it does seem possible. The shape of the intake horn itself seems like it might pose a problem with being airtight though. The stock intake horn is actually pretty restrictive anyways. Right where it connects into the grid heater it gets fairly rectangular. Seems like there is some room for improvement there. What I would like is to find is an intake horn like the one you have . After waiting on hold with Banks technical assistance line for a half an hour and still being the 3rd caller in line, I started looking into other solutions.

Holy hell, don't move the master. Build your own elbow like was mentioned. You obviously have a welder and some fab skills. Cut a 3/4" plate to square, hole saw it to whatever you want. And weld a mandrel elbow clocked however you need.

This is the avenue that is currently being explored. Just checking into materials and designs. Aluminum seems to be an ideal material for heat dissipation and corrosion resistance. It would have to be TIG welded though. Not something I have direct access to. Stainless steel, same story (IIRC). So, that leaves something with the possibility of corrosion. A legitimate concern here. I believe the stock intakes consist of a cast aluminum. There is a place called Pusher Intakes. They seem to have a good product and I have been emailing them about this. They seem willing to come up with solution and are better equipped than I am to do so. The owner himself is the one corresponding so that is pretty cool .

There is another option that might help. There is a grid heater delete that would put the intake an inch or two lower. Not sure if this really helps and I would have to come up with a way to preheat for cold starts. Haven't really looked into this option a whole lot yet because it would have to be some sort of a combo solution. Used with a small body lift, it may give enough clearance to use one of the stock intakes.

 

[CUCV2]

Here's an overhead pic of the clearance issue and one of the stock intake horn. Elongating the holes might be worth a shot.

 

[Greg72]

Hydroboost conversion would get you all sorts of extra space.....

Didn't realize you were still using a vacuum-boost brake setup.


-G

 

[DEMON44]

Holy hell. I though you already had hydroboost as well. Do that hydroboost conversion right quick. Besides you don't want to be relying on that ****ty vacuum pump for your brakes.

 

[CUCV2]

That makes sense. Now I just need to figure out how to convert my 71 K5 with a 93 Dodge brake booster to hydro boost. Probably, not a big deal if they offered hydro boost brakes in the 93 Dodge Cummins. I am surprised that the truck this engine came out of did not have it. Seems like hydro boost brakes and diesel engines usually go hand in hand. Why is that? Seems like it has something to do with gas engines generating more vacuum.

 

[DEMON44]

Exactly.


Just use GM hydroboost. And get custom lines made up if you have to. That's all I did when I had the 12v in my 98 Chevy dually.

 

[ashman]

lots of us have done the hydroboost conversion into a first gen, so plenty of pics laying around and brains to pick if needed.

If it would help I can measure how far my MC sticks out from the firewall with the hydroboost so you can get an idea of how much clearance you'd get.

 

[CUCV2]

Exactly.


Just use GM hydroboost. And get custom lines made up if you have to. That's all I did when I had the 12v in my 98 Chevy dually.

lots of us have done the hydroboost conversion into a first gen, so plenty of pics laying around and brains to pick if needed.

If it would help I can measure how far my MC sticks out from the firewall with the hydroboost so you can get an idea of how much clearance you'd get.

There is a CUCV hydroboost down in the shed... wonder if that would work.

The only issue I have with this plan is that it will add some twist into getting parts. The majority of the parts have all been 93 Dodge. If not that then the 71 K5. If there are brakes out of an 86 CUCV, it may be an issue down the road as far keeping track of what parts are from what. I guess the keep it simple (KISS) plan went up in smoke when the Cummins went in .