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Discussion Starter · #1 ·
Hey all, new here and trying to get pointed the right direction. I have a 95 Bronco in really good condition with a 351 auto. I am less than impressed with this combo so I would like to do a 4BT/ZF5 swap. I am not a fan of tracking down parts all over the place for dirt cheap. I would much rather have a few reliable sources to get everything from but I don't even know where to start. Any help would be appreciated, thank you!
 

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I did this swap with my 94 bronco from 351 auto to 4bt/zf5. It is straight forward but you will need to source a few things. What you will need: Both Drivelines-Transmission crossmember for the manual- Clutch pedal assembly- Clutch master cylinder/hydraulic line/slave cylinder. That is all because of the ZF5 is shorter then the e40D. You can reuse the transfer case. Save the 351 harness and the e40d harness. They will make the rewiring for the ZF5 and 4bt easier. if you have the electric push button transfer case then the e40D harness will need to be rewired so the transfer case shifts 4 high and 4 low. It is also used for the neutral safety. Then you will have to figure out radiator hoses and power steering hoses. Also using a GM SI alternator simplifies the alternator part.
 

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Discussion Starter · #5 ·
I did this swap with my 94 bronco from 351 auto to 4bt/zf5. It is straight forward but you will need to source a few things. What you will need: Both Drivelines-Transmission crossmember for the manual- Clutch pedal assembly- Clutch master cylinder/hydraulic line/slave cylinder. That is all because of the ZF5 is shorter then the e40D. You can reuse the transfer case. Save the 351 harness and the e40d harness. They will make the rewiring for the ZF5 and 4bt easier. if you have the electric push button transfer case then the e40D harness will need to be rewired so the transfer case shifts 4 high and 4 low. It is also used for the neutral safety. Then you will have to figure out radiator hoses and power steering hoses. Also using a GM SI alternator simplifies the alternator part.
Thank you for the info. Did you piece everything together or were you able to find some primary sources? I have all the mechanical skills to do this but my shop setup isn't ideal for re-builds etc. I really would like to find all the major components that are just ready to bolt-in.
 

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Thank you for the info. Did you piece everything together or were you able to find some primary sources? I have all the mechanical skills to do this but my shop setup isn't ideal for re-builds etc. I really would like to find all the major components that are just ready to bolt-in.
Most of it was pieced together for a different project then the bronco fell in my hands. As for me, I did a custom mount for the tranny and was able to reuse the rear driveline and had to remove 1 inch on the front. My bronco has a 4 inch lift. Alot of what I got was local expect the cummins SBF adapter/flywheel/starter that was ebay.
 

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Discussion Starter · #7 ·
Most of it was pieced together for a different project then the bronco fell in my hands. As for me, I did a custom mount for the tranny and was able to reuse the rear driveline and had to remove 1 inch on the front. My bronco has a 4 inch lift. Alot of what I got was local expect the cummins SBF adapter/flywheel/starter that was ebay.
Gotcha, I live in NE Oregon and there isn't much for resources here. Sounds like I will need to start piecing things together.
 

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One thing you haven't mentioned is what power level you plan on. Your OEM 351 has 210 HP and 325 lb ft of torque. A base VE pump 4bt has 105 HP and 265 lb ft of torque. As you can see, the diesel is more about torque than HP. Many guys aim for the 200 HP point on the 4bt which will give you in the neighborhood or 450 lb ft torque. It would feel like you put a 460 V8 in there. The engine actually weighs about the same too so some HD front springs would be in order. To obtain that power you'll need to do a few mods to the engine. #1 would be get a better turbo. The stock VE pump 4bt came with an H1C turbo. Change it to a HX30W and that part of the project would be in order. On the injection pump side you need a few changes. Install a 3200 RPM governor spring. You won't be running at that speed but it makes gear changes better. Ideal operating speed for a 4bt is in the 1700-2000 RPM range. Most shoot for 1800 RPM. That's the point of the most torque and best fuel economy. Next you need to turn up the fuel level and finally adjust the timing advance a bit. Don't overdo those last 2 items. You don't need bigger injectors to reach 200 HP. Always wise to have them checked to be sure they are in good condition. Weak injectors can make for a poor performing engine. Anther item you'll need to work out is brakes. Your Bronco has vacuum boost power brakes. Diesels don't have manifold vacuum like gas engines. You have 2 basic options. #1 is install a vacuum pump on the engine for you system. #2 is install hydroboost brake booster which runs off the power steering pump. The hydroboost unit found on the F Superduty diesel would be a direct bolt on for your body style if you wanted to go that route. You may find other issues that crop up during a swap. Just have to address them as they show up.
 

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Discussion Starter · #9 ·
One thing you haven't mentioned is what power level you plan on. Your OEM 351 has 210 HP and 325 lb ft of torque. A base VE pump 4bt has 105 HP and 265 lb ft of torque. As you can see, the diesel is more about torque than HP. Many guys aim for the 200 HP point on the 4bt which will give you in the neighborhood or 450 lb ft torque. It would feel like you put a 460 V8 in there. The engine actually weighs about the same too so some HD front springs would be in order. To obtain that power you'll need to do a few mods to the engine. #1 would be get a better turbo. The stock VE pump 4bt came with an H1C turbo. Change it to a HX30W and that part of the project would be in order. On the injection pump side you need a few changes. Install a 3200 RPM governor spring. You won't be running at that speed but it makes gear changes better. Ideal operating speed for a 4bt is in the 1700-2000 RPM range. Most shoot for 1800 RPM. That's the point of the most torque and best fuel economy. Next you need to turn up the fuel level and finally adjust the timing advance a bit. Don't overdo those last 2 items. You don't need bigger injectors to reach 200 HP. Always wise to have them checked to be sure they are in good condition. Weak injectors can make for a poor performing engine. Anther item you'll need to work out is brakes. Your Bronco has vacuum boost power brakes. Diesels don't have manifold vacuum like gas engines. You have 2 basic options. #1 is install a vacuum pump on the engine for you system. #2 is install hydroboost brake booster which runs off the power steering pump. The hydroboost unit found on the F Superduty diesel would be a direct bolt on for your body style if you wanted to go that route. You may find other issues that crop up during a swap. Just have to address them as they show up.
Thanks Char, I am a diesel guy all the way, have a 20 Duramax, 18 Cummins and 99 7.3 sitting in the driveway right now. That's the only reason the 351 is coming out is I don't like gas motors.....at all. I appreciate your advise though and will likely do the larger turbo.
 

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Actually, the HX30W isn't larger. If you get the 44mm version, the compressor side is about the same. The big difference is the turbine side. The small H1C found on the 4bt came with either a 16cc or 18cc non gated housing. The HX30W has a 6cc gated housing. Boost comes on much faster and can go higher. The only larger turbo that works with the 4bt is the Super HX30W which has a 46mm inducer and the same 6cc turbine housing.
 

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Discussion Starter · #11 ·
Actually, the HX30W isn't larger. If you get the 44mm version, the compressor side is about the same. The big difference is the turbine side. The small H1C found on the 4bt came with either a 16cc or 18cc non gated housing. The HX30W has a 6cc gated housing. Boost comes on much faster and can go higher. The only larger turbo that works with the 4bt is the Super HX30W which has a 46mm inducer and the same 6cc turbine housing.
Copy that, thank you.
 

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I am from central oregon. With all the dodges and ford's around here getting parted out I don't have to hard of a time finding parts. My 4bt is a ve pump with a h1c. I do have a 3200 rpm spring in it but it is very slow to spool. My bronco sits higher in the front with the 4bt then 351 by 1.5 inch's nothing was don't to the suspension.
 

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Yes, the turbo spool from that H1C is slow and has top end limits. It does OK with the base 105 or 120 HP engines but is no real performance turbo. Turning up the fuel to try to get it to boost more generally only results in more heat and little power improvement. When Cummins introduced the P pump version they changed to the HX30W which is light years better. Many of the industrial 4bt's with the A injection pump also got that turbo. Don't understand how you suspension could have gotten higher with a 4bt. The 351W weighs 510 lbs and a 4bt is around 750 lbs.
 

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Char1355. Yes they 4bt does weigh around 750+ I honestly would say I wonder what springs the PO has in it.
 

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Discussion Starter · #15 ·
Well I finally found a 4bt VE already mated to a ZF5 S-42 and manual transfer case. It's being delivered late next week so the fun will begin soon. It has a saginaw PS pump and GM alternator on it already. My preliminary list of things to find now are:

Engine and tranny mounts
New Driveshafts
HX30 Turbo
Hydro boost
Clutch/Brake Pedal Assembly
Intercooler?
New Radiator?


I know I am missing a lot of things, just trying to get started. If anyone wants to add to the list that would be really appreciated.




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Discussion Starter · #17 ·
Thought I would post an update. Progress has been slow going as winter lasted longer here than usual and work has been insanely busy. But I have the engine in, radiator hoses, a/c, heater hoses, throttle cable, cruise control cable and new clutch/brake pedal assembly with heim joint all complete. The only item really holding me up is the power steering. None of the local hose fab companies in my town can figure out how to make me a hose to go from the Ford gearbox to the 3/8 inverted flare on the back on the Saginaw pump......crazy.
 

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.... The only item really holding me up is the power steering. None of the local hose fab companies in my town can figure out how to make me a hose to go from the Ford gearbox to the 3/8 inverted flare on the back on the Saginaw pump......crazy.
130655

Bought a Ford power steering hose that matched my F150 PS box.
Bought a Dodge power steering hose that matched the Saginaw PS pump from a Dodge diesel.
Carefully fitted both hoses for clearance, selected a convenient point to cut the hoses.
Had the auto parts store crimp on a coupler fitting.
Lots of years and miles - no problems.

Russ
 
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Thought I would post an update. Progress has been slow going as winter lasted longer here than usual and work has been insanely busy. But I have the engine in, radiator hoses, a/c, heater hoses, throttle cable, cruise control cable and new clutch/brake pedal assembly with heim joint all complete. The only item really holding me up is the power steering. None of the local hose fab companies in my town can figure out how to make me a hose to go from the Ford gearbox to the 3/8 inverted flare on the back on the Saginaw pump......crazy.
Look at these guys...
 
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