chevy leaf's UNDER frame on a b2

[spdcrazy]

Ok so the next project on the B2 is a chevy leaf swap UNDER the frame. I picked up a 8.8 the other day so I need to weld on the new spring perchs and shock mounts. I have more research and measuring to do but I have a few questions i'd like to get answered while i'm learning. I plan on a reverse shackle setup on the back and a standard pivot point up front. Max flex is the goal. Not sure if I want to do a 63 or 64in because i'd like to keep the axle position the same so I don't have to do anything with the driveshaft or wheel wells. Ok here's a few questions for ya, sorry if they seem kinda scattered.

1.assuming a 63in leaf, should I look for a 1500 chevy spring or a 2500, etc? Something light weight? And with the suggested leaf, whats the eye to eye measurement with a load on it, hopefully the load of a chop top b2 with a light 4point roll bar, but I can prob make it work if I had the measurements on a ranger or something similar.
2.What angle should the shackle be on the back with a load on it? I assume it needs to angle to the center of the leaf a bit, but how much? I plan on using a custom length shackle, similar to the 6400 beltech. But that will change when I get everything together, so I can attempt to get the ride height I want, as well as a good amount of flex.
3.On the brackets to hold the leaf on, I plan on cutting them myself and having a shop weld them up due to lack of a welder and trust in my welding too. What thickness should I look at? 3/8in? Mild steel I assume. And should the regular pivot piece be one single piece of steel and bent into a U or three pieces welded together for the U shape? I don't plan on any amount of drop on the front pivot point FYI.
4.If things work right i'll be at about 6in of lift (plus or minus 2in, i'm not real picky) so what is the general rule of thumb on pinion angle? And how do I set that without knowing exactly the ride height with a load on it?
5.Should I consider boxing the frame where the brackets will be for the pivot points for the leafs? Its no desert racer, just a rock machine with little highway use, but if it should be done now is the time.
6.on the shock mounts, I messaged dan from ruff stuff a few days ago, waiting on a response, but maybe you guys can help. I hate how the stock 7.5 had the shock mounts that hang below the axle housing, is there any negitive effects to mounting them level with the axle so they don't get smashed by rocks? I would keep the stock configuration of one in front and one behind the axle. does anyone make something that I could use, or would I be best just fabbing them myself?

 

[spdcrazy]

anyone, bueller... bueller.... bueller....:icon_welder:

 

[BONES]

Well, I'm not the answer guy for most of your questions but I do know that you will want to leave the pinion angle for last, with the weight on the vehicle.

Your rear drive shaft tcase flange has an angle to it when measured with an angle finder, with the vehicle sitting on level ground with the weight of the rig on the springs, you want your rear diff flange to be plus or minus 2 degrees from the rear tcase flange measurement. This will be on a 2 joint drive shaft, one joint at the tcase and one joint at the diff. Any more than 2 degrees will put the 2 ujoints out of sync and you will get a vibration at speeds.

If your running a CV rear drive shaft you will want the diff flange to point up towards the tcase about 4-5 degrees below the rear tcase flange.

Your shackle angle should angle forward up to the frame from the rear of the leaf spring, like you said angled towards the center of the spring, maybe say 20 degrees with the weight of the vehicle on the springs. You want it angled far enough so the shackle doesn't invert under droop and also so it doesn't limit compression, should find the happy medium if there is one.

Welded or bent leaf mounts doesn't matter as long as it's welded properly or bent properly. 1/4 or 3/8 is plenty strong enough. I wouldn't worry about boxing the frame, the old Jeeps (cj2-cj3-cj5-cj7-cj8) used the same set-up with leafs mounted directly under the frame and had C channel frames, they survived OK with that set-up and larger tires. I'm not telling you not to box the frame, I just don't think it is necessary.

When I swapped in the 8.8 under mine a while back I cut the shock mounts off the 7.5 and did exactly what your talking about, having them level with the ground instead of hanging down, worked good. The one in front and one behind the axle shock arrangement was intended to help prevent axle wrap and wheel hop. Not completely necessary, the stock Explorers have the shocks both at the rear of the axle angling towards the center and rear of the vehicle slightly.

Hope this much helps.....It's all I got.

 

[spdcrazy]

good info, pretty much thinking the same as you are.

i think i'll box the frame on the back, just because i can build it into the rear shackle hanger. prob use 1/4 and NOT bend it, just weld three pieces together, because its easier to weld on a 90 then bend with the tools i have.

i need to figure out a way to play with where the front hanger is to be located. my thoughts were to weld the rear shackle mount because i am limited on its location. then mount the leaf up and see where the front should be on the frame. that way i can put the weight of the truck on the leaf and get my angle right. thoughts?

 

[spdcrazy]

ok i took a wheel off and got some measurements, its looking good. couple of other questions, whats the width of the leafs of the 63in chevy's?

and can someone grab the measurement from the front eye to the center bolt on a 63? also from the back eye to the center bolt? this will help tell me if i'll have driveshaft issues.. i'm sure i will, but if its only by an in or so i can compensate for it in how i build things.

i'll be doing some more research tonite, but anyone know the diameter of the 8.8 off the top of their head?

 

[spdcrazy]

looks like the front mount on the 63 swap is going to be all the way up under the body mount!!! gonna be huge!

also, any recomendations on shackle length? i was going to go 6in, but with how things look i think 4 might be better for height, then again i want max flex. im worried because right now the rear hanger is gonna be hanging down about 8in from the bottom of the frame!!!

 

[RangerSVT]

The problem with doing a 63 swap on the B2's is the body mount has to be modified/removed or have a custom under-the-frame hanger as mounting the hanger with the body mount there is not possible, as they both will occupy the same space...
SVT

 

[spdcrazy]

The problem with doing a 63 swap on the B2's is the body mount has to be modified/removed or have a custom under-the-frame hanger as mounting the hanger with the body mount there is not possible, as they both will occupy the same space...
SVT

yes, that is the major problem, hence why i'm looking into putting them UNDER the frame...

 

[RangerSVT]

I have a friend that just bought a B2 for a trail rig and I have an idea that I was tossing around, feel free to try it. If you are going to or have done a 3" body lift, get you a piece of 1x3x3/16 tubing, about 4 foot long (measure from outside the body mount to outside the body mount and this is your length), remove your stock body mount brackets, and mount the tubing on top of your frame and drill the appropriate holes to mount your factory sized mount to. You may have to add a washer or two to get the height needed, be sure to measure from the original bracket before removal to see exactly how much steel you need to use, it may end up being 2 inches thick instead of 1 inch thick, but you get the main idea. Yeah you could run two small pieces, one on each side, but there would not be enough support without some type of bracing underneath, but then you run into the hanger mount, defeating the purpose. If you do this, be sure to take plenty of pics and do a very detailed writeup, as no one has thought of this yet and will become a very popular swap amoung the B2 crowd, I dont currently own a B2 but use to and I thought about it a long time ago but have gotten rid of my B2 which I regret and want another one. But the idea and simplicity should be very easy to do:icon_thumby:
SVT

 

[spdcrazy]

I have a friend that just bought a B2 for a trail rig and I have an idea that I was tossing around, feel free to try it. If you are going to or have done a 3" body lift, get you a piece of 1x3x3/16 tubing, about 4 foot long (measure from outside the body mount to outside the body mount and this is your length), remove your stock body mount brackets, and mount the tubing on top of your frame and drill the appropriate holes to mount your factory sized mount to. You may have to add a washer or two to get the height needed, be sure to measure from the original bracket before removal to see exactly how much steel you need to use, it may end up being 2 inches thick instead of 1 inch thick, but you get the main idea. Yeah you could run two small pieces, one on each side, but there would not be enough support without some type of bracing underneath, but then you run into the hanger mount, defeating the purpose. If you do this, be sure to take plenty of pics and do a very detailed writeup, as no one has thought of this yet and will become a very popular swap amoung the B2 crowd, I dont currently own a B2 but use to and I thought about it a long time ago but have gotten rid of my B2 which I regret and want another one. But the idea and simplicity should be very easy to do:icon_thumby:
SVT

hey that sounds like a pretty good idea. however, i don't really want to do a body lift. and the chevy leafs under the frame appeals to me more. still need to source the leafs and get them in my hands to take a closer look before i start making phyical progress with this. i'll keep ya updated tho.

 

[RangerSVT]

still need to source the leafs and get them in my hands to take a closer...

88-98 chevy 1500 full size trucks is what your looking for:icon_thumby:
SVT

 

[spdcrazy]

88-98 chevy 1500 full size trucks is what your looking for:icon_thumby:
SVT

ya i got that figured out, but i still need them in my hands!!! then i can start fabbing my brackets that i have drawn up

 

[spdcrazy]

for search purposes,

seems to be that the correct shackle angle would be a bit less than 90 degrees from the spring angle. at least in a regualr setup, i assume its the same for a reverse shackle?

 

[RangerSVT]

With the vehicle weight on the axles, sitting level, a reverse shackle setup (front) has an angle a little greater than 90* to the frame (leaning away from the axle)...
SVT

 

[spdcrazy]

ok i picked up my 64's today. might be 63's. don't really care, but i'll measure them and get back to ya. cost me 35 a piece. 70 total. so rusted i had to cute the shackles in two with a torch at the junkyard.


god i need my torch setup...

next is to build shackles. then pivot brackets, fix the hole in my floor board, etc....

the leafs came off a 1500 extended cab chevy. idk what year but prob mid 90's

 

[spdcrazy]

ok i decided to ditch the reverse shackle idea because i would have had about 8in of steel mounted solid to the frame and hanging down on the very back edge, just waiting to grab a rock. with a standard shackle setup, i will be able to adjust height pretty easy, and will help me keep my wheel base the same with these chevy leaf's.

i'm going to build my own shackels instead of use 6400's, that way i can make them parallel, that way when i need to replace bushings, i can just get six chevy leaf spring bushings and call it a day.plus fabbing the shackles will be cake!

its tough finding someone that will weld the brackets on here in flagstaff, might have to drive to phx to get it done.

 

[mazdafamily]

i just put chevy leafs under my mazda b2600, they were 63 inch leafs i arched them 5 inches the went really nice under my frame and all most looks stock

 

[spdcrazy]

i'm still looking into this, tho the light seems to be dimming, with the fuel tank sitting pretty close to the frame i'm thinking i'll run into issues with lateral movement on the leafs, debating on having some new flexy leafs built and running a custom drop bracket in the back and adding just a bit of length as well. of course i'll build it where i don't have to use the block also