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Discussion Starter #1
Ok guys figured I might as well get the build thread under way so here goes I’m swapping in a 4bt Cummins out of a 1974 P30 Chevy and a 95 GM NV4500 and swapping in newer 1 ton axles. Here’s some pics
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I have the choice to run the dually rear end from the P30 or the SRW full float axle. So let me know what y’all think and why one axle over the other. Now sit back and enjoy the show;)
 

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Discussion Starter #4
I have the choice to run the dually rear end from the P30 or the SRW full float axle. So let me know what y’all think and why one axle over the other. Now sit back and enjoy the show;)
 

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If you use the dually rear, you can use your existing front dual wheels, or with singles on the rear, singles on the front will be too wide, unless you get special offset fronts.

Ed in CO
 

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Well guys been doing a lot of reading on here researching is on of my favorite things to do believe it or not. My goal with the engine is to be at 200hp I think that will be plenty for my needs in this 1 ton. I have to check what turbo I have I would like to be able to just upgrade it vs buying a new one if possible. I did read a thread that said with a good turbo and a pump tune I can run it stock and be at that number I’m not sure what IP pump I have I’ll have to check that as well. I don’t haul 20k trailers and never will. I never hauled that kind of weight with my Bobbed m35a2. The engine was very clean for as long as it sat did not smoke at all exhaust was very clear.
 

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Ok found 2 different part numbers for the GM Cummins flywheel Cummins Flywheel 3906802 & 3918055? Will both work? I read some threads here but did not have any clear answer to that.
 

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Well guys I’ve been looking at different things online to try to get a better understanding of what I have and what i need to get. What can I do with the current turbo and IP pump I have to bump up the HP?
 

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Well I have the VE pump and watched some videos on how to tune it. Is there any thing I can do to the stock turbo to upgrade it? I also want to know if I need to change the stock injectors?
 

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First off on your flywheel question. The number 3918055 is someone misreading the number. It is 3913055. The number 3906802 shows to be a good number also but that may be the bare flywheel without the ring gear which is part 3905909. Could also be an older manufacturing number. Cummins often changes a part number when they change suppliers. On the turbo, 3802347RX is the H1C turbo normally found on the 4bt. That RX indicates is is a rebuilt unit. That turbo will not be what you'll want on a 200 HP engine. Get yourself an HX30W either the 40mm, 44mm, or 46mm Super. The 44mm would probably be the best bet and cost a bit less. Figure roughly in the $600 range for the turbo plus you'll need the outlet elbow and clamp. Here's a listing on ebay for one to give you an idea of what to look for. Beware of the very low priced turbos. They are not genuine Holset units. New Genuine Holset Turbo HX30W 6cm2 T3 4040353 4040382 - Ships from Texas | eBay Your injection pump 0 460 424 045 was a common one on the 105 HP engines. It can be turned up to get your to the 200 HP range. One mod that you'll probably want is to install a higher RPM governor spring. Most use 3200 RPM on the VE pump. No need for new injectors but you'll need to have those tested to be sure they are in good order. If they don't check out good, you can have them rebuilt or replace with rebuilt units. Another thing to include in your plans will be an intercooler. The 4bt's above 105 HP had one of some type. Making more power takes more fuel and more boost which creates more heat. Hot air makes poor power. Compressed air coming out of a turbo can exceed 300 deg F.
 

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Discussion Starter #14
Ya I’ll have to look into having the injectors checked. I saw the cheap turbos will avoid those. I’ll have to keep an eye out for an inter cooler of some sort. It would be nice if I could upgrade the turbo I have. Is there anything I need for the ip pump other than turning it up saw you could rotate the fuel pin. What would be a better turbo/ fuel setup for a heavy rig like mine and not a Jeep. I read I can leave everything else stock for that HP goal of 200hp.I also plan on running a snorkel pipe to the outside to get fresh cool air.
 

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Most snorkel intake pipes are so contorted so as to reduce airflow. Just route your engine compartment intake to get outside air directly.

Ed in CO
 

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Well hit another snag I don’t think the NP201 transfer case will hold up to highway driving even if I weld the knock gear I may have to find an NP202 or an NP205:/
 

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On the turbo, there just aren't any mods for that small H1C that will make it a good one for a 200 HP engine. The problem is the large turbine housing with is usually 16-18 CC without a wastegate. Boost comes on slow and no matter how much fuel you add it's is just a dog. The smallest gated housing for that one is 12 CC. In comparison, the HX30W series has a 6 CC housing. Boost comes on super fast and will build past 30 PSI. The H1C was just an obsolete turbo and was replaced in later engines.
 

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Very good to know ya as far as the transfer case goes I test welded the broken knock gear I had yesterday and it’s just too brittle to risk running it especially with a diesel and read all over the net about the overheating issues after the driveshaft goes over a certain RPM ends up melting the seals. I just don’t want to chance that. I have been looking at the NP 202 and NP 205 and just been searching around to see if I can find any deals on that elusive GM flywheel and been watching for a D60 front with the leaf springs that hasn’t been hacked on or welded on. Once I have these items out of the way this show can really get started lol.
 

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Very good to know ya as far as the transfer case goes I test welded the broken knock gear I had yesterday and it’s just too brittle to risk running it especially with a diesel and read all over the net about the overheating issues after the driveshaft goes over a certain RPM ends up melting the seals. I just don’t want to chance that. I have been looking at the NP 202 and NP 205 and just been searching around to see if I can find any deals on that elusive GM flywheel and been watching for a D60 front with the leaf springs that hasn’t been hacked on or welded on. Once I have these items out of the way this show can really get started lol.



I have a gm flywheel on my motor, it's a 93 and had the factory gm nv4500 behind it. Pulled that pos off and sold it. Gotta pull the flywheel and swap block adapters.send me PM maybe we can figure something out.
 
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