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Discussion Starter · #1 ·
I am getting close to completeting my swap in my early bronco 72, My question is what suspension setup up's did you go with in the front. I am looking at these different types of coil springs and see that there are progressive rates, varible rates, linear rates, and constant rate. Height of lift you put in the front compared to rear would be great. How much did your setup sag in the front say if you used 5.5" coils and what type of coils where they?

My current setup is all 1972 stock suspension and with the motor tranny and t-case in, the nose sits 2.75 inches lower in the front then the rear. I also did the oilpan mod by moving the sump over towards the passenger side and with just the motor in there it looked to clear no problem but with the tranny and t-case it looks like it it is only 1/8 from hitting the front differential. Any help or sugestions would be greatly appreciated thanks.
 

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Depends on what the rig will be used for. I'm building a 1990 F150 and putting in a '79 straight axle in the front. I'm going with 34" tires and 4" lift coils probably constant rate. This truck will mostly be on road so I don't need the super flex type coils that are good for off-road. I've read that the progressive wound coils tend to sag more than the constant rates. You need to go to www.fullsizebronco.com and pirate4X4,com, there is a ton of info on those boards about suspension. You set your front lift based on tire size you're running and intended use then adjust your back height with blocks or aftermarket lift springs, rear shackle flip, etc.
 

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I went with front leafs on my '66. I added a Dana 60 front, 15,000lb PTO winch, and the 4bt. These components add up to considerable sprung and unsprung weight of which I felt coils would not be the best solution for my use. To increase flexability, I added "orbit eye" bushings on the fixed spring hanger at each corner.
 

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I would talk to Chuck at BCBroncos.com. He has several different spring rates in several different heights. He should be able to steer you toward one or the other. I think if you install his without scratching them and are unhappy with the stance, he will exchange them.
 

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Discussion Starter · #5 ·
anyone who's done this swap in a early bronco wanna share what their setup is?
 

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Yeah

I started with 3.5, but it was too high, and even with 7 degree shims, castor was still not totally right, and I didn't want extended I beams, cause I.m cheap and it was too tall for me too. Handling sucked.. My wife complained because she had trouble stepping into the Bronco. I wanted what husbands want, so I decided to lower it. Now, I am running 35" tires with 3.54 so my ratio is about 2.78 which keeps my RPMs in range.
Dropped it to stock, and cut pan to match. Still set that way, but the pan to differential spaciing is 2" and I dont feel comfortable.
I have a set of 2.5" springs to correct the spacing.

Since you've trimmed your pan, you know you can only triim it so much, till you're trimming the oil pickup to and really cutting oil capacity.

So whats the answer. When you set the engine in, and fabricate your mounts, you can set it high, cut a hole in the hood to keep suspension low, or jack the suspension up (no hole in hood), correct the castor issues, cut the pan put whatever springs you want. Bottom line, there is no EB recipe. Custom conversions are done to suit.
How tall you set your suspension is related to how tall your wife is, or your girlfriend, and how much you want what most guys want in relation to driving an old EB.
Wayne
 

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I tried 2.5 progressive rate coils in my '74 EB but the weight of the 4bt pressed right through the soft progressive part of the coil. I'm gonna try some old school stiffy Rancho or Superlift 3.5's and see if they work. I'm hoping the added weight of the 4BT, plate bumper and winch will "soften" the ride of the Superstiff coils a little.
 

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i would stick to the newer style softer coils and go with a linear rate spring instead of the progressive rate. and if you have a heavy bumper and winch along with the 4bt would start with the spring that is an 1.5" taller then you want for total lift should get you close

scott
 

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I'm working on a 4BT into a 1971 Bronco. I have an older James Duff 3.5 inch lift installed with the straight coil springs.

I actually had the 289 mounted on the frame when I decided to swap to a 4bt. Frame with 289 weighs 2098 and the frame with a 4BT weighs 2370 for a difference of 272 pounds. The engine, adapter, and bell housing are the only differences.

The diffeence in height between the two was 3/8 inch measured at the frame front cross member.

Hope this helps.
 

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Discussion Starter · #10 ·
I got the lift put on the bronco early this week, ended up with deaver 5.5 linear rate soft ride coils, jeffs 3.5 inch rear leafs. ended up just about level maybe a little higher in the front. i have not yet been able to drive it do to some wrong transfercase seals being sent to me. I am going to attach some pics the front is down about an inch and a half because my shock hoop has not yet arrived so i compressed it down and reconnected my old shocks. Pretty happy with the look of the lift also has a 2 inch body.
 

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I'm just getting started with a swap in 1972 Bronco. Bought Bread truck with 4BT and T19 4spd. What parts will I need to put NV4500 in?
 

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I used a progressive 5 1/2" coils up front and a 11 pack, double eye wrap 5 1/2" leaf spring Wild Horses setup on mine. D60 hipin front axle no pan mods. 5" bumpstops.Thought front end would be lower but sits perfectly level.
 

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I'm full width but didnt need to be.Pumpkin would have stayed in the same place. Im running a NP205 and wanted shaft parallel with framerails. Like I said in previous post 5 1/2" susp. lift, 5" bumpstops, could actually run 3" and still clear pan.My engine is tight(1/2") on pass. side framerail. Not using stock starter so gained some room. Its possible, jump on a creeper and look.:D Check my sig.
 
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