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4BT 1969 Bronco

robsim111

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Mar 3, 2016
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34
Hey y'all. I figured I would stop in and show what I've started on (which I haven't gotten far.) I purchased a 69 Bronco from Louisiana about 10 years ago. It was in rough shape, and I had never worked on a vehicle in my life. It's been a long journey of forum hunting and buying tools.

Anywho, I ended up having to pull the motor that came with it because it had a crack in the block. It was a Torino 302 mated to a 4 speed Toploader transmission. I replaced it with a bone stock ATK 302, mated it to a rebuilt AOD that I mated to the original Dana 20. I ended up adding FiTech, which was meh. I never noticed a difference in economy or power. I finished the bodywork myself, and since it wasy first time was a 20 footer for sure. Especially considering I painted it with a Wagner power sprayer.

Right before Covid, I figured I wanted to sell it, so I took it to a bodyshop to redo the body so all of the tire kickers wouldnt come criticize it. The had it for a year and a half, and turns out he had just left it out in his back lot with the top off through 2 hurricanes and no telling how many storms. It was basically ruined. I came and got it in a rage. I decided to just keep it, and I pulled the body all the way off and pulled it apart.

Since I've had the body off, I degreased pressure washed, degreased, pressure washed and then sanded the frame. I left light rust, and I POR-15d it. I also did a 4 disc brake conversion and remade all new steel brake and fuel lines.

However, I purchased a 4bt to put in it right before I replaced the motor in it with the ATK. I did not put it in though, because I was incapable of any sort of fabrication or any sort of modifications that weren't bolt in. So I've been sitting on it. I've been extra bored, so I pulled the entire drivetrain, and decided to put the 4bt in. I'll add some pictures to show where I'm at, and start asking my million questions.
 

JB Fab

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Subscribed,,,,, We've got a couple of 4BT AA Broncos.....

#1 most important bit of advice I can give you, is to use the liquid filled Lord engine mounts.
 

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robsim111

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Mar 3, 2016
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Okay, so I don't have any pictures from when I picked it up from bodyshop, because I was sick to my stomach.
But here are pics of the frame now. You'll see I had to cut the motor mounts and front crossmember out. I welded up a new crossmember, and moved it forward to accommodate the Cummins. The guy who had it before me went nuts with a flux welder. Took me forever to grind the crap down.

 
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robsim111

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Mar 3, 2016
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So here's where I'm at. How the hell do you fit it low enough to clear the hood without sitting on suspension? I have a 5.5" suspension lift as well as the rear sump pan. Also, I have a Cummins adapter mated to an nv4500, so the starter is HUGE. I was going to go compare to the planetary type in a 4th gen 6.7, because they have same dimensions and teeth and bolt pattern. Definitely do not want to notch the frame. It was easy enough to make a new crossmember and move forward to have clearance lengthwise.
 

JB Fab

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Yes, front holes, there is another style that is even further forward (typically used in gensets and marine applications).
Using the front holes leaves room to use the cam drive for air compressors and/or hydraulic pump etc. (you loose your location for mechanical fuel pump when you use too many things on the cam drive accessory port).
I made the ones shown in the previous pictures.
Fitment in relation to what specifically?
 

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robsim111

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Mar 3, 2016
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I accidentally deleted your comment instead of my duplicate.

But, I posted some where you can see the starter sitting on the frame, and the motor side bracket in front of it. Also posted one of my holding a motor mount by the passenger side bracket.
There were no holes except the weld burns the guy added. I'm pretty sure the mounts I'm going to put on the frame will be the 4th set it's had. There are no motor mount holes though.
 
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robsim111

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Mar 3, 2016
Messages
34
Yes, front holes, there is another style that is even further forward (typically used in gensets and marine applications).
Using the front holes leaves room to use the cam drive for air compressors and/or hydraulic pump etc. (you loose your location for mechanical fuel pump when you use too many things on the cam drive accessory port).
I made the ones shown in the previous pictures.
Fitment in relation to what specifically?
I was trying to avoid the front mounts as it makes it puts more stress on the bell housing. I purposely traded a vacuum pump style PS pump for a pancake style for that reason. Also, I'll be running hydroboost, so I'm not too concerned about the pump. I have the 25 gallon EFI fuel tank from BC broncos, so the electric pump will be in tank.
 

JB Fab

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Getting the frequency of your mounts wrong would have way more of an effect on bellhousing stress than using the front holes, besides you would have to try pretty hard to mess-up the bellhousing with a 4BT in a 5000lb Bronco (I have a bit of experience engineering stressed components, and my daily driver is a 4BT) NOTE: This one is not my daily....
 

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robsim111

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Mar 3, 2016
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Getting the frequency of your mounts wrong would have way more of an effect on bellhousing stress than using the front holes, besides you would have to try pretty hard to mess-up the bellhousing with a 4BT in a 5000lb Bronco (I have a bit of experience engineering stressed components, and my daily driver is a 4BT) NOTE: This one is not my daily....
I understand. I assumed that based all of the research done on 4btswaps that people shouldn't use front mounts locations, but it looks like that's the way to go as far as an EB is concerned. What is the part number for the hydraulic motor mounts you used?
 

JB Fab

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I don't know off the top of my head but they are from a Freightliner P-30 Step van
 
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