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Discussion Starter #21
Well been looking at transfer cases I am leaning towards the NP202 it has the same pattern as my current PTO and I can bolt it up fairly easily as I have both an IH np201 and the dodge np201. The np202 also has the through shafts like the np205 and is stronger than the 205 and no knock gear or overheating issues like the np201. I am trying to line up a d60 front still and will have a GM flywheel one way or another with or without another adapter plate which I’ll sell with the flex plate and automatic transmission I currently have. I’ve also been looking around for the holset HX30 or hx30w even a good core to rebuild. The Miss and I will probably be making another road trip for parts ?
 

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Discussion Starter #22
Well been doing a lot more reading on turbos and also looking at the HX35 lots of used ones everywhere at very good prices and will be better than what I have currently the stock H1c. My truck is a heavy rig anyway and driving a Bobbed M35a2 since 2012 I think it’ll be more than satisfactory for this build. I am hoping to just do gaskets seals 3200 gov spring and a pump tune and cleanup n paint.
 

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…I am hoping to just do gaskets seals 3200 gov spring and a pump tune and cleanup n paint.
Is there an Exhaust Gas Temperature (EGT) gauge in your plans? Your aluminum pistons will thank you.
 

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Discussion Starter #24
Yes I have one in my M35a2 as the egts in 22:1 Multifuel engine go to melt down in a real hurry with no pump or turbo mods I have it set up with water injection wired to the gauges alarm which in turn actives a voltage sensing relay which turns on the the water injection pump. I ll probably have the same setup on this build. I scratch built it. I could go post or preturbo. Preturbo has to have the nozzle as close to the impeller as you can get and the spray must be dead center to prevent droplets from forming or it will chew up the fins. If you go post turbo if you have an inter cooler you must go to the exit or the mist will fall out of suspension and pool in the inter cooler. I will set all that up before the truck is ready for the street.
 

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On your turbo choice, don't think on an HX35W for a 4bt. Not a good match. It's too big. You do find tons of those on the market due to the fact they were on a lot of 6bts. The HX30W will be the best choice. Finding a used unit to rebuild may prove a bit of a task. In the US, the only models used were the 40mm and 42mm. There are several versions of each out there. The 40mm versions came on the P pump 4bt and some of the industrial 4bt's. The 42mm, which is much rarer, came in 2 versions. One had a 12cc turbine housing and was used on a industrial 6bt. There was a 6cc version was on some industrial 4bt's but that one is not common. Your best bet would be a 44mm HX30W. Physically, looks identical to the 40mm. It is an import only turbo. Most commonly found coming out of China, but those are genuine Holset units. Generally, will cost in the $550-600 range. Go down to the Cummins store to buy one and you may be looking at near $2000. Beware of super cheap ones. Those are usually clones and not the genuine item. The last member of the HX30W family is the 46mm which is call the "Super". That's the largest single turbo that works on a 4bt. It is also an import and never came on a Cummins. It will cost a little over the $600 price point. All of these except some of the 42mm come with a 6cc turbine housing. All of them have T3 exhaust flange so they will bolt to any stock 4bt exhaust manifold. All except the 46mm would use the same oil line as your H1C. The 46mm is different in a lot of ways. Different oil fitting, 4'' air intake instead of 3", and larger air outlet on the compressor housing. On most of these you will also need the compressor outlet elbow and clamp.
 

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Discussion Starter #26
Ya I did read that the hx35 was on 4bts that were 250hp and some have said they run better than stock turbo but 600$ or 2000$ turbo is not in the cards atm and I definitely am not buying any of the eBay knockoffs. I’ll take my chances with the HX35 for now. I still have to buy a D60 front axle and a flywheel that costs a ton and a t case That is streetable at highway speeds. I don’t drag race or beat my vehicles up or have no need to roll coal so I’ll be fine for now.
 

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That 250 HP engine was a marine application. That was a water cooled HX35W. You won't like the HX35W. It will be slow to boost and has a very narrow power band on the top end only. Generally results in higher EGT's. The 4bt just doesn't produce enough exhaust gases to spool it properly. When the injection pump is putting fuel into the engine and there's not enough air to burn it properly you only get heat and not power.
 

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Discussion Starter #28
I thought I read guys were running it and the owner of this site said it was able to be run. I’ll have to check the stickies again. If I’m not able to run it I’m just gonna run what I got for now as that turbo is impossible to find used and is way out of my budget for a good while.
 

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Discussion Starter #29
Ok guys been very busy getting these parts lined up. I just worked out a deal on the monster NP202 transfer case. I also got an awesome deal on a GM Dana 60 front and an amazing deal on a brand new flywheel for the Chevy Cummins.
 

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Discussion Starter #30
I also wanted to make a separate post for the flywheel to help keep others from being ripped off. I think 750$ +for a used flywheel is a rip-off and those selling them at that price ought to be ashamed of themselves. I’ve never in my life sold parts at a rip-off price and always pride myself in giving good deals. Here’s where I got the flywheel (BRAND NEW) First Motion Products in Missouri 573-468-3840. Here’s the part number 3906802. I payed 498$ plus around 50$ shipping. They as of today have 48 of them in stock. They were very nice on the phone and got me taken care of. So I hope posting this will help others on there future builds and or repairs and keep and put there hard earned money to good use and give it to honest folks. Thanks for all of the input and information everyone has and continues to give here on 4btswaps and I hope I can help too as my build progress continues.
 

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Discussion Starter #31
Ok guys I picked up my GM d60 front it’s got the dually hubs have to measure it tomorrow it’s in good shape with need lockouts but 400$ bucks can’t complain. I ll have to get some pics and do some videos.
 

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Discussion Starter #34
I have not purchased the turbo yet as it might be too big. I also got the dually rear end pulled out of the bread truck. I haven’t checked it yet but it might be a 14 bolt as well as the other axle I have. We are working now to get the front grill off to pull the 4bt and trans out.
 

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Yeah, that is an HY35W. A bit too big for a 4bt. Came on a 24 valve 6bt in a Dodge. An HY30W is a small turbo similar to an HX30W. Not extremely common but they do show up from time to time. I believe the HY30W may have a T25 exhaust flange which would need an adapter to fit the T3 manifold common on a 4bt. Below are photos of the HY30W and an HY35W.
 

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Discussion Starter #37
Ya I figured it was when I searched the numbers online so I didn’t purchase it. I’ll keep looking for one at a reasonable price or try to trade for one. I’m hoping to pull the motor and transmission today all in one go and split them when they are out. Trying to do it while there’s a break in the weather supposed to be rain later again ugh:/
 

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Discussion Starter #40
Well guys we got the engine separated from the engine and got it ready to the gaskets seals and paint. I will be doing everything but the head gasket. I am wanting to know as far as the Gm NV4500 should I just do gaskets and seals or do the bearings and synchros as well. I am doing gaskets and seals in the NP202 as well. Also are the gear sets in all the same in all gm 14 bolts? 73 and up?
 
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