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Possible other option, drop the turbo.
Put a spacer between the turbo and exhaust manifold, would still need to modify the inlet piping. That could just be an extension to clamp to the turbo housing and sort out any alignment problems. Should still have enough height for the oil drain to work. May need a longer oil feed line..
Cheers Steve
 

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Thanks Mark. I'm always a bit puzzled as to which generation is what in those Dodge Cummins. I knew the WH1C was only offered that one year and then they changed to the HX35W. That 1st photo I posted is actually a 1st generation turbo with that elbow mounted. The one in the second photo did come with a WH1C which I have. Do you know what year they changed from having the turbo back plate and elbow separate to a 1 piece design? I'm guessing it was in the 1998.5-2002 24 valve engines.
 

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Discussion Starter #23 (Edited)
Seeing the view from that angle throws out another possible. There is a down pipe that was found on the WH1C turbo which will bolt right up to the HX30W. If it doesn't hit the firewall it would work perfectly. Here shows on on a turbo. As you can see it is angled. I have one of those in my parts pile. The second photo is the one I have and show a side view.
Here are some better Pictures of the angle of the firewall w/ the turbo mounted Low & then mounted high;

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Yes, camera angle changes the perspective of the situation. Member Steed had a similar problem with his first build on a 2002 Toyota. His solution was to use the Cummins manifold 3901635 in a flipped position. Doing this puts the turbo in a much lower position but also requires using a remote oil filter setup as you see in this photo. Here is another possible solution. Get a blank back plate for the turbo in 1/2" steel. The one shown in the photo below has an ID of 2.9" and costs $27.20. Get a 2.5" tight radius schedule 40 pipe elbow. That has an OD of 2.875" and comes in plain steel or stainless. Then weld that pipe to the flange. Beware that one of the bolt holes may be under the elbow so that hole may need to be slotted to the edge. The overall width of that elbow is 4.32" but you have eliminated the flange coupling on the back of the turbo. Acerace sells the mild steel elbow for $15.95. Then you could add a length of schedule 40 pipe to the elbow to drop down. Overall cost would be minimal compared to other options. Just a bit of welding involved. Might be worth taking a look at.
 

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A 1st gen Cummins 2wd down-pipe is the tightest pipe available after the full marmon 4" cobrahead, from the images above it will be your best bet, once fitted remove it and have it ceramic coated inside and out, or DIY, once coated it can be wrapped or covered w/o usual damage caused to wrapped pipes.
 

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Subrutus, don't think the 1st gen pipe would make it. It's 3" and even with the tight bend it's going to be more than 4". Also, I believe you'll find the 4" cobrahead is a half marmon, not a full. Half marmon has 2 flat surfaces where the full has a flared pipe and a taper to match it on the other side. See photos.
 

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Selling 4bt & 6bt parts to all of N.America
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Thanks Mark. I'm always a bit puzzled as to which generation is what in those Dodge Cummins. I knew the WH1C was only offered that one year and then they changed to the HX35W. That 1st photo I posted is actually a 1st generation turbo with that elbow mounted. The one in the second photo did come with a WH1C which I have. Do you know what year they changed from having the turbo back plate and elbow separate to a 1 piece design? I'm guessing it was in the 1998.5-2002 24 valve engines.
That 1st pic maybe a 1st gen turbo but someone installed that elbow then, as I can insure you the 1st gen dodge cummins had no elbow from factory.

The change up to a one piece elbow was in 2000 year.
 

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Subrutus, don't think the 1st gen pipe would make it. It's 3" and even with the tight bend it's going to be more than 4". Also, I believe you'll find the 4" cobrahead is a half marmon, not a full. Half marmon has 2 flat surfaces where the full has a flared pipe and a taper to match it on the other side. See photos.
Well, thank you, I seem to have had a brain f__t...
 

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That 1st pic maybe a 1st gen turbo but someone installed that elbow then, as I can insure you the 1st gen dodge cummins had no elbow from factory.

The change up to a one piece elbow was in 2000 year.
Here is a 4" 1st gen 2wd down-pipe to a 35.
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Selling 4bt & 6bt parts to all of N.America
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Selling 4bt & 6bt parts to all of N.America
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2wd Late 1st gen (21cm not 18cm) may be the tightest but leaves a lot of extra between the full marman and the 90° , the extra distance I cut off my pipe is the amount the hx35 with backplate moves the V band aft of the h1c ~1-2"
Taking the blasted taper off my hx35 changing it to 1/2 marmon give ya 1/4-1/3"

A non gated housing would free up some space

What part of the states ? SLC +-500mi and id drop off the 3" 91.5(jun) system. I could bring the welder and steal a piecut off of the DP if necessary.
Flow is the master but his mistress has too tight of curves causing separations to occur... it fits in a box is more important than it performs topshelf.
 

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I had a similar problem on a 6bt squeezing the exhaust between a non wastegated HX35 and the oil filter. As Char suggested I used a cut down tight steel elbow and welded a matching flange into it. The 3" elbow then had a second one welded to it to take the exhaust back towards the rear above the engine mount.
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Oka, that's a very nice job. Don't see that center drop 6bt manifold very often but it does exist. He probably wouldn't have any issue with the oil filter since his turbo is mounted much higher but would need the pipe made just like yours. The problem then becomes air plumbing. The air intake wouldn't be a problem because there are cobra head units for that. Most of the 4bt's in the delivery vans had one. The compressor outlet would take a bit of studying to work out. The turbo doesn't care which way it's pointing. I've even seen 6ct truck engines with the reversed position.
 

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Char the manifold is fitted to lots of industrial 6BT's, in fact my engine in the pic is a 2009 STORM block built as a mechanical engine for a genset, took a bit of mucking around sourcing the necessary bits to turn it into a vehicle engine including a "new" VE IP. I welded a V band to the end of the bottom elbow and then a flexi joint to connect to the rest of the exhaust.
The intake is a silicon elbow specifically made for the NT Oka and connects it to a Optiair cleaner. The tab on the bottom picks up the engine mount to take the weight off the turbo and manifold
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The NT Oka intake hose goes from the 5" Optair outlet down to the 3" turbo inlet and makes a neat job of the intake side.
 

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Yes, a flex coupling is a good idea on a diesel and especially the 4bt. It's vibration is considerably more than your 6bt. On your exhaust manifold there there 2 types. Yours if for the turbo in the low position and there was on for it in the top position. You can tell them apart by the location of those threaded bosses. They are always on the top side but no rule says you can't mount one upside down. I also found an interesting exhaust elbow. I believe this one is from the ISDe engine. Part 4939408 is a very tight elbow. I know the half marmon flange on the small size fits an HX35W so it would also fit an HX30W. Question is how big is that bottom flange. There is a bolt boss on the back that could be ground off. You can tell the the overall size is no more than that bottom flange. Might have possibilities. My guess would be close but would have to have one on hand to know. When mounted to the turbo that larger flange is partially under the turbine housing. Price on ebay is $45.12 + $22.00 shipping from China. Here's a photo of an ISDe 6.7 that has that pipe. Although that turbo is in reversed position, you can see how the pipe fits. Like I said, this has possibilities.
 

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Discussion Starter #39 (Edited)
I received the ISDe exhaust elbow yesterday (prt# 4939408); And it is a tight fit, with less than 1/8" clearance to the firewall. This is a dam sham as I could have spared a 1/2" more clearance to the front, before engine mounts where placed...... I did have to remove the threaded boss; the bottom flange measures ID 3.5" OD 4.5"

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One plus is it does clear even though it is tight. Might need a small dimple in the firewall if more clearance is desired. If you're worried about heat transfer there you could have it ceramic coated. A bit expensive but that would make the heat almost nil.
 
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