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1955 Brockway 155W Continental to Cummins Conversion

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26K views 108 replies 11 participants last post by  speedfreak440  
#1 ·
I’m sure most folks here are not familiar with Brockway trucks, but they were manufactured in Cortland NY from 1912 to 1977. They were bought by Mack in the mid 50’s and were an ‘autonomous’ company until the day they closed in 1977. They have a very loyal following and there is an annual truck show dedicated to Brockway’s the second Saturday of every August.

My Dad drive truck for a living and always had an interest in Brockways. I bought my 1955 155W in 2000 and spent 8 years restoring it. In 2008 we drove the truck for the first time from near Scranton PA to Cortland NY for the annual show. I So far I have put a little over 7300 miles on it. Even with having 2 other Brockways, a 361 and 761, I really enjoy driving this truck. So I decided it was time to make a few changes...

This forum has been very helpful with some issues I ran across with my Cummins 6BT so I figured I would share my build thread here. This starts in the fall of 2015...

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The 42BD or 427 flathead Continental has been a great motor but really doesn’t have the power you need for today’s roads. It will run 55mph all day long on level road but once you hit any kind of grade your down to 40 in the right hand lane with the 4 ways on. I would like to be able to run 60 mph up a hill so I decided it would be a good time to upgrade the Continental. I did consider making some upgrades to the 427, like adding dual carbs with the Ellis manifold, maybe an MSD ignition, a Mallory distributor, etc., but most of these upgrades would have little gains verses the costs. It’s also start to leak some oil so that was another deciding factor...

So after much thought I decided to replace the Continental with a 5.9 Cummins. They are comparable in size as well as weight. I did consider the 8.3 Cummins but that weighs in at 1800lbs which is about a 1000lbs heavier than the Continental. You can also build decent power fairly economically with these motors. I also knew that these were used in some smaller Freightliners with air brakes so that was a plus since (air compressor, etc...)

More to follow...
 
#52 ·
In addition to the steering box, I got the 2 yoke ready that connect the steering column to the steering box...

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After removing to old ujoint, I sandblast both pieces and bought a new joint from Napa...

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For reference, these are the same joints in the 300 series...

U Joint – Napa UJ861 or Neapco 1-1475

To help hang the box to paint it, I dug out a part that I used to hang the steering column from my Dad’s 361. I wound up cutting the end off of a steering shaft that was really rusty.. But for this purpose it worked fine...

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In the mean time I started to gather the other parts I needed to paint. This included the front end brackets that bolted the front crossmember and springs in...

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Since I heavily modified the front crossmember I decided to sandblast the hole piece...

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More to follow...
 
#53 ·
I also sandblasted the other pieces and then gave them a coat of self etching primer where they bolted together. The pieces fit pretty tight and I would never be able to put everything back together without really scratching it. So I felt this would work best...

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For the P7100 injection pump, I wound up sending it to Industrial Injection in Utah. I already went this far with the motor so it only made sense to go through the pump. I did call a couple of local places and really didn’t get a warm and fuzzy feeling from them. When I talked to the guys at Industrial Injection, they discussed everything they do to the pump. This included replacing the delivery valves, changing the governor spring out to 4k, replacing the fuel place if necessary, etc, and then calibrating and testing the pump. They also built 6 new injectors to match the pump.

After they received the pump and took everything apart, they called to tell me that someone had messed with it and some parts were bent and the fuel plate was missing. So it was a good idea to have this gone through after all. They did give it a coat of Cummins beige so I sure hope it doesn’t react with my paint. This would be a tough piece to strip all the paint off of...

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Prior to getting it ready for paint I did removed the throttle linkage, etc. I will need to work on that later...

Another large piece I needed to paint was the air compressor. The motor originally came with a Bendix Tu Flo 550. I felt the compressor should be rebuilt so I looked at a few kits. The parts were fairly expensive but I wound up finding a new one on eBay that was reasonable priced, so I would up buying that one... The best part was the “MADE IN USA” part on the aluminum tag...

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This compressor had a fitting on it that would allow you to pull air from the air cleaner. I didn’t want to go that route so I found the same type of filter set up that I used on my Dad’s 361. Bendix calls it a strainer, part number 278500...

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More to follow...
 
#54 ·
So we spent last Saturday getting everything ready to paint and then all of Sunday painting everything. All in all, we able to paint the air compressor, injection pump, fuel shut off solenoid, new steering column, alternator and idler pulleys, oil fill tube, revised front crossmember and brackets and the rebuilt Ross steering box...

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#57 ·
WOW is just about the only word to describe this build. Extreme attention to details and you have a great shop with tools to handle the job. One thing I was curious about. Your water pump appears to have a billet aluminum pulley. Wondered where you found that. I was thinking all the factory pulleys are iron. My eyes are still watering from enjoying this build.
 
#61 ·
I hope you can find room for a large enough CAC in front of your water radiator, I have a '37 GMC with a tall, narrow nose like yours, and I had to search around quite a bit to find one, intake and return out the bottom, I had plenty of length in front of the radiator. JWC are not very useful since they start out with 180F water as the cooling(?) agent, but spacing can be difficult with our old trucks not designed for I'coolers, good luck.

Ed
 
#64 ·
Now that everything was painted we were ready to start the reassembly process. We started with reinstalling the modified front crossmember. Once that was in place we were able to rehang the front springs and then set the front end back down on the ground...

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The Bendix Tu Flo 550 is fairly heavy so we used the cherry picker to install that...

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At that point I realized there was a bracket that was mounted behind the compressor that is used to support the rear of the injection pump. So the compressor came off again and then I installed the bracket. This motor is like putting a puzzle together, everything has to be done in a particular order...

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Once the compressor was back on we installed the injection pump...

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After the injection pump was on, I realized 2 things... first, the oil feed line that serves the pump would be almost impossible to install with the pump in place and second, the #8 AN to 14mm fitting that comes with the FASS fuel pump kit is way too close to the air compressor, as you can see here...

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So it looked like the injection pump would have to come off again. Meanwhile I ordered some #4 Aeroquip teflon hose and fittings to make the new oil feed lines for both the injection pump and the air compressor. While I was waiting for those, I decided to work on the thermostat housing, etc. When I started dry fitting everything, I realized the Cummins gasket set did not include the correct thermostat gasket or the correct lower water neck rubber seal. I did order those parts a while back so now everything was ready to go...

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More to follow...
 
#65 ·
I installed a new 180 deg thermostat along with a new belt tensioner and the idler pulley (this idler pulley is were an ac compressor can be installed in the future...)

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The only thing electric on this whole motor is the fuel shut off solenoid. I did have the option of replacing this with a cable but I thought I would leave it as is for right now. It uses a weatherpack connecter so I had to order the other end. I wound up getting both a male and female it. It turns out the plugs are ‘keyed’ with small slots in them, so I wound up cutting the plug right off the solenoid and using the new one from the kit I bought...

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Once the #4 fittings and hose came, I started making the new lines for both the injection pump and air compressor. The short line pictured here is for the injection pump...

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You can see here where the oil lines are fed from. Once the injection pump is installed, there are very difficult to reach, let alone with a wrench!

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More to follow...
 
#66 ·
Once the lines were done, I decided to make a bracket for the throttle cable and exhaust brake switch. I figured it would be much easier with the pump on the bench. I was fortunate that this motor came from a Ford F800. The Dodge pickups use a large bracket that mounts off of the injection pump to work the throttle. I’m not sure it would fit with the air compressor. The Ford used a steel rod (just like the traditional Brockway trucks used). I wanted to reuse my Lokar pedal so I make a bracket to bolt to the injection pump...

I started with a piece of 1 1/2" angle...

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I then welded a piece of flat stock to it to mount the micro switch to control the exhaust brake...

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And then I welded the factory bracket for the return spring to it...

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And here is the finished product...

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For the micro switch, I used the factory Jacobs switch that came with the Jake I bought for my Dad’s 671. On his truck I bought an updated buffer switch. The Pac Brake kit did come with a micro switch that was designed to be mounted under the throttle pedal. I am going to use this switch for my clutch pedal. The Pac Brake wiring diagram lists the clutch switch as optional, but I want one for my truck.

I also mentioned that the fuel inlet fitting that came with the FASS kit would not clear my air compressor. The fitting that came with the kit was #8AN to 14mm. The original pump was fed with a banjo fitting that was #6 or 3/8”. But I needed a fitting that was either a 45 or a 90. I couldn’t find what I needed at Napa but a friend of mine told me about www.discounthydraulichose.com. They are located in Philly and carry a ton of specialty fittings. They didn’t have and 14mm fittings for #8, but they did have 16mm. It turns out that these P7100 pumps have helicoils in them to reduce from M16 to M14. A lot of guys remove them for high horsepower applications where they need more flow, etc... So I ordered the fittings and was able to carefully remove the helicoil...

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I realized the 90 wouldn’t work but the 45 appeared that it would work... So last night we reinstalled the pump and boy is it close! I did screw on a hose end and there is plenty of room...

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More to follow...
 
#67 ·
On a side note, we also installed my rebuilt Ross TA66 steering box. I really hope this box work well, but in case it doesn’t, I do have a plan in place to add power steering. When I bought the motor, it came with a ZF power steering pump attached to the back of the air compressor.

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I also talked to the folks at Sheppard and it looks like a 492 box may work but I will have to change the pressure regulator within the ZF pump.

In the meantime I decided to install the Ross box...

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I also talked to the world’s foremost expert on the removal and installation of Sheppard power steering boxes in Brockways, Brian Enck. Brian made a lift hook that would screw into the top npt port on the box. I made a similar mount for the Ross and it balanced the box nicely. Then we used the cherry picker to help set it in place. This box isn’t very heavy, but the cherry picker and a long chain certainly made it easier to install...

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Well that’s it for now! Stay tuned for the next episode of Millard & Sons Garage...
 
#68 ·
When we last left off we had finished installing the injection pump along with the Ross TA66 steering box. One thing I wanted to mention was that we had to time the injection pump to install it. To bring the motor up on top dead center I picked up a boring bar off of Amazon, OTC 7174A. This sure made it easy to turn the motor and get everything lined up...

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To install the pump, I followed this procedures listed in these (2) pdf’s...

http://www.dcpcart.com/files/P7100_Install_Instructions.pdf

http://oregonfuelinjection.com/pdf/inline-cummins-pump-removal-and-installation.pdf

After the pump was installed we installed the pump gear and the torqued it to the right setting using the boring bar to prevent the crank from turning. After the nut was torqued, I installed the fix for the ‘killer dowel pin’. I installed this even though I believe it has the updated case there the hole is slightly smaller on the outside to prevent the dowel pin from backing out...

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The next thing we worked on was installed the front crank seal in the cover. Since my crank had a groove wore in it, I decided to use the wearseal kit from Cummins, #3802820. The kit did not come with instructions and it wasn’t too easy find out the correct procedure online. After some searching found out that you never lubricate the seal with oil or it will ruin it. Also, you have to use red Loctite to seal it and press it in from behind with the supplied tool. This is the piece in the lower right hand corner of the pic...

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I used the press to just ease the seal in place, it doesn’t take too much force...

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The white nylon piece in the lower left hand corner of the pic above is used to help slide the seal over the crank without damaging it.

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After you install the front cover, then you pull the nylon sleave out and install the dust ring, which is in the upper right hand corner of the pic above.

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The dust seal is a tight fit and the damper helps push it on all the way. I wound up buying a Fluidamper since my original damper had a ding in the outer cover and I didn’t want to take a chance with it. So we installed the damper and trial fit the serpentine belt. When I changed the alternator brackets, I needed to get a longer belt. I went with a 2” longer belt (as shown in this pic) which is too long. I wound up replacing it with a 1” longer belt...

For reference, the Napa Belt part numbers...

25080830 83.755" (original, too short)
25080842 84.799" (1” longer, just right)
25080852 85.75" (2” longer, too long)

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More to follow...
 
#69 ·
The next thing we moved on to was setting the radiator in place. I needed to figure out the fan along with the hoses. The original fan was 24” in diameter and was too big for the radiator which is only 23” wide...

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The plastic fan had this part number on it... 4035-40518-03 and had a 5” hole with a 6” bolt circle. After looking that number online, I found this website...

http://www.kit-masters.com/fan.php

The original Continental fan was 19” in diameter so I put my dimensions into that link to find the correct fan. I wasn’t able to get a 19” fan, but they did have a 9 blade fan that was 20” in diameter. I wound up with this part number, 4735-43480-11 and was able to order it from finditparts.com.

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The original fan clutch was fairly tight and appears to be in good condition so I decided to reuse it. After I got the fan, the bolted the fan in place and set the radiator on the truck...

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The Cummins is a few inches shorter that the Continental, and the center of the fan is about a 1/2" lower that the Continental. It turns out they made a number of different fan mounts for the 5.9, and I was fortunate that the one from the F800 Ford was (I believe) this highest one they made. And this placed my fan almost in the same place as the original. Regardless, I would still need to make a few fan shroud.

If you remember, we wound up making a new shroud for my Dad’s 361. So I decided to make one similar to the 361... The fan is about 1.5 degrees lower than the radiator, so the new shroud would have to be angled somewhat. The original fan shroud is angled also but its deceiving by looking at it. I revisited the pics from the 361 build and picked up a new sheet of 18 gauge sheet metal...

We started by shearing a couple of angled pieces for the sides...

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And then bent the front and back flanges...

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Then we trimmed the flange to fit the radiator and then drilled the 6 mounting holes...

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After bolting the side pieces in place, we bent the outer piece to fit over the sides...

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After that piece was fit, we took everything apart and drilled a series of 3/16” holes so that I could plug weld the pieces together...

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Once the sides were welded, it was time for another trial fit...

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More to follow...
 
#70 ·
I made a few corner pieces and then plug welded them also to keep everything rigid. After that, we set the radiator and shroud back on the truck...

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When then taped some cardboard on the shroud to mark the perimeter of the fan...

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Once I was happy with the location the radiator came back off the truck and I figured out perimeter of the opening...

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Flex-A-Lite has a nice write up on the correct design for a fan shroud (https://www.flex-a-lite.com/blog/the-perfect-fan-shroud-position/) so I based my design on that. Basically the hole is 1” larger that the diameter of the fan and the fan is half in and half out of the shroud.

My overall opening is a little under 23” so the circumference is a little under 72”. Since my brake is only 4’ wide, I sheared two 36” long piece that were 3 5/8” wide. I needed a 1/2" lip to fold over on both sides and I added a 1/16” on both sides for the sheet metal thickness. My brake can only do to maybe 120 degrees or so, so I wound up using the hydraulic press the finish the fold to complete the outside lip...

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After the inside lip was bent in the opposite direction, I used a long piece of angle, clamped the two 36” sections to it, welded them together and smoothed out the weld...

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Then I marked both the slots I would need to cut and the holes I would need to drill. I decided to cut a slot every 3/4"...

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After a lot of drilling and slot cutting with the cut off wheel, we wound up with this...

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More to follow...
 
#71 ·
Once the ‘ring’ was done, we moved back to the main piece. We wound up cutting the round hole with the jig saw...

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Once the whole was cut, we moved back to the ring. I’m guessing it makes sense now why we cut all the slots?

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The ring will overhang the bottom of the shroud slightly so we had some trimming to do. I also straightened the tabs on the side to make it fit. This was our final trial fit...

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After a series of plug welding we were able to trail fit the shroud back on the radiator...

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It’s a bit skewed on the bottom but that will straighten out after I make the filler piece.

Well that’s it for now!
 
#72 ·
When we last left off we were finishing the new radiator shroud. I needed to make a filler piece for the bottom where the opening overhangs the bottom a bit. As with the 361 shroud, I used the shrinker tool to curve a piece to fit...

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After a little tweaking, it fit pretty well so I plug welded it in place...

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After everything was done we set the radiator back on the truck to see how it fit...

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Now that the radiator shell was done I turned my attention to the radiator hoses. On the Continental, the top hose was 1 3/4” for both the upper and lower hoses, but the Cummins uses 1 3/4" for the top and 2” for the bottom. The top inlet on the radiator came out a few inches and then pointed down towards the motor...

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But his wouldn’t work now since the upper connection is not centered on the Cummins, it on the passenger side of the motor. So I went out and looked at an older grill and radiator I bought from a junkyard over 15 years ago. The top water neck was 1 3/4" and pointed straight out so I felt this would work...

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I also looked at a 260 parts truck I have but the 572 uses a much larger hose, probably 2 1/2". I also had a re-cored radiator from a 257 and I put in a crate and set off to the side some time ago. The lower water neck was 2” so I decided to use this part as well...

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At the end of the day these wound up being the parts I needed...

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More to follow...
 
#73 ·
The lower neck had a fitting brazed into it that used a compression ring, so I wound up cutting part of the fitting off, drilling and tapping it for a plug. A cap would not have worked since it would have fit my new shroud...

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For the hoses, I did consider going to my local Napa and trying to find hoses that would work. But after much thought I decided to go with silicone hoses from FrozenBoost.com. They offer a number of different sizes, colors and angles and lengths so I figured this would be easier. I order enough fittings, joiners and clamps for both the top and bottom hoses.

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I started with the top hose and with a little trimming of the 45 bend, I was able to put this together. We did install the grill and strut bars to make sure the radiator was in the correct location before we started working on the hoses...

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The bottom hose was a little trickier but I think it worked out ok...

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More to follow...
 
#74 ·
Next on the list of things to do was the turbo and exhaust manifold. My motor originally came with an industrial or RV style manifold that places the turbo down, between cylinders 4 and 5. Some applications used this manifold flipped upside down so the turbo would be on top, between cylinders 2 and 3. I felt this would work for me for 2 reasons. First, my starter is on the passenger side (like the Continental) and the down pipe would wind up dumping directly into the starter. Second, there is plenty of room on top and a ton of clearance to the hood, and with the turbo being closer to the front of the engine, this would give me some more room for my downpipe.

This is the manifold that came with the motor but unfortunately it was cracked and at one time one of the turbo studs must have broken. Someone drilled the hole crooked and used a bolt instead of a stud...

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At that point I decided to replace it with a new one from BD Diesel, part number 1045989. This is their 2 piece pulse manifold which flows better and supposedly is less prone to cracking since it’s 2 pieces...

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The turbo that was on the motor was a Holset WH1C and although it felt tight, it was beyond rusty. I considered rebuilding it but decided to replace it with a different one. I talked to the folks at Industrial Injection, who rebuilt my P7100 injection pump, and after discussing the cam I used, etc. they recommended their PhatShaft 6270. This is basically a Borg Warner S300 with a 62mm forged milled compressor wheel and a 65mm turbine wheel. ..

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I knew I was going to need a spacer to clear the valve cover, so I installed the new exhaust manifold and set the new turbo on top. I needed about an inch and a half of additional space so I wound up buying (2) T3 1” spacers from Mayhem Metal Works. These guys were very helpful and have a ton of different spacers, adapters, etc. These are also ported to match both the manifold and the turbo.

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Once I received the spacers, we installed the turbo and started looking at the oil feed line to the turbo. Cummins originally used an inverted flare flex line. The size was 12mm x 1.5 so I wound up buying some #6 adapters. These fitting use orings and the first ones I bought did not work. They were not made to be used with an oring (second from the right). The original fittings are the 2 on the left and the correct #6 an fitting is on the far right...

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More to follow...
 
#75 ·
Now that the turbo was on I decided to start working on the exhaust. Even with the turbo located between cylinders 2 and 3, I realized the downpipe would still be close to the fire wall. The original WH1C turbo was designed for a 3” downpipe, but the Borg Warner 300 was designed for a 4” pipe (HX40). I wound up buying downpipe designed for a 89-93 first gen Dodge Ram...

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It sure looked like it would fit based on the pics. I talked to the manufacturer and that was the tightest HX40 pipe they made. I did a little more research and found out that Cummins made a cast ‘cobra head’, part number 3927862 or 3927882. These were factory on 8.3’s and are designed for the 4” HX40 flange. I found one of those on eBay and bought it with the hopes it would work...

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Although it gets fairy skinny, it does neck out to compensate for the difference in area. I did set this on the turbo but wasn’t sold on it. It’s a cast piece so I can’t weld to it (unless someone else did it for me...) On a side note, a lot of guys use one of these when then run twin turbos. They use it for the ‘hot’ pipe.

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At that point I did consider modifying the 89-93 downpipe I bought. But I changed my mind and bought just a plain HX40 flange and a handful of 4” Walker mandrel bends from Napa.

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I was really pressed for space so after studying a few articles on building custom headers from scratch, I came up with an idea. I started with a 4” 90 deg bend that had a 4” radius (the tightest radius they make...) I had about 6” of clearance between the turbo and the firewall and the HX40 flange is about an 1” thick. So I wanted to trim about an inch off of the 90 bend. To help mark the cut, I cut a 4” hole it a piece of template cardboard...

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I slid the cardboard pattern down the bend until it got tight and then drew a line on the pipe. The pattern helped me figure out how much I could cut off before the hole became oval. Keep in mind I need to stay perpendicular to the end...

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After some cutting and filling, I was able to trial fit the piece to the turbo... Now we’re getting somewhere!!!

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More to follow...
 
#76 ·
My next task was to cut another 4” 90 deg bend perfectly in half. This time I used a 5” radius 90 since I didn’t need to be as tight as a 4” radius. Using some foam backboard from work and a quick cad sketch, I made a jig to fit over the bend...

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I had marked the center of the 5” radius on the jig to help me find the center of the pipe. I then cut the 4” cardboard hole I made in half and used that to mark the pipe...

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I did used a hack saw to make the cut since I don’t have a band saw and there is no practical way to clamp it in the hydraulic hack saw. It’s worth the extra time, the cut came out great...

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With my 2 bends and some painters tape, I was able to mock up my new custom down pipe...

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Once I had the pieces correctly lined up, I tacked everything together and started welding...

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More to follow...