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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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You could throw whatever springs under there you wanted to, some F150 springs from a big block engine'd truck would probably get you close to supporting the extra weight, without sitting too funny.


If you really want to do it right, get it weighed. Take it to a truck stop, or better yet, borrow a set of scales from a racer buddy. Once you know exactly what that weighs, you can subtract the weight of the axles, wheels and tires, and you now know what your 'sprung' weight is.

Call your favorite spring supplier, and now armed with this information, you can find some springs that will ride well, still flex, and suppport the engine. Chuck @ BC Broncos is very good at springs, and can get custom coils for you. It'd be worth a call down there to talk to him.

www.bcbroncos.com

Hope this helps.
 

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My guess is that out of the 4 types you list: progressive rates, varible rates, linear rates, and constant rate

progressive and variable rates are similar, and linear and constant rate are the same.

Progressive have a tighter wind at the top of the coil, it should be progressive because the spring rate changes progressivly as the coils are spaced closer together. These "should" ride better, i'm not sure that would be the case with a 4bt in there. Linear/constant rates should be the same coil rate throughout the length of the coil, at least that's my guess.

When it comes to what Gummi Bear was talking about, spring rates are key. that is if you can find out what they are. for linear rate coils, its pretty easy, it's always in in/lbs. this means if you put 1000 lbs on 2 coils that are rated for 200 in/lbs, the coil will compress about 2.5"
 
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