New Member Questions

[72k5mike]

Hey guys! I've been a "silent" member around here for quite some time and have finally decided to join. I have an orange '72, 350 SM465 NP205 D44/12bolt on 35" KM2's. I have had this truck for a few years now and I will be creating a build thread soon.

In the mean time I want to pitch an idea out there. I have recently started creating brackets for a rear 63" spring swap and it got me thinking. I have been planning a front coil conversion using some early br*nco coils (probably progressive rate) but would a front 63" swap be worth while? I know that there are some length issues with the springs, but would I be able to mount the leaves backward in the front (rigid mount in the rear and a shackle on the front similar to jeep and ford.... a shackle reversal if you will)? I mostly use this truck for beach running on Long Island, but it does see the occasional offroad trip to trails or rocks. Let me know what you guys think

 

[bp71k5]

Welcome. Super flexy springs on the front sound a little scary on the street, but who knows about sand. Ive never driven on sand, but is a soft suspension really useful for that? Let's see some pictures!

 

[Greg72]

63" up front sound like a bad idea. Think about how are forward your front spring hangar is going to need to be, and what that will do for your approach angle.

My guess is that your spring hangers will stick our further than your front bumper.

 

[72k5mike]

Well Im not really into driving too fast on the sand, but where I go, everyone doesnt "air down" as much as they should and in turn tear up the sand.

Greg, I should have been a bit more thorough in my idea. If I were to mount the 63" springs in normal fashion with the fixed mount forward, I would have to put the mount about an inch forward of the front bumper. I was tossing around the idea of rigid mounting the rear of the spring and putting the shackle in the front, hoping that the angle of the shackle would compensate for this extra inch or so.... Just an idea i was playing with

I guess what i was hoping to spark here was some discussion of the advantages/disadvantages of the GM style rear shackle vs the f*rd and J*ep front mount shackle

 

[Greg72]

A shackle in the front of the spring is a pretty bad idea too.

For a stock Jeep that doesn't actually wheel, it works; but the design requires the axle to move FORWARD to get any flex. If you're trying to climb a rock, the tire won't want to move forward because the obstacle is in the way....so no flex, it will just lift the entire corner of the body instead. If you do get up on the rock, the weight of the body will immediately push the axle forward to flex the spring, and the body will then come back down quickly....transferring weight at a time when you probably don't want it to be moving much.

If you happen to be approaching a BIG rock, the last thing you're going to want is to be making your first contact with a shackle (with your front-mounted idea). It's much safer to hit it with the fixed end of the spring and then let it slide a bit until the tire is able to get traction and start climbing.

I don't know what your ultimate plan is for the truck, but this option you're talking about sounds like a bad one from a few different perspectives. You can flex like mad using a more conventional spring setup....I've posted pics of my truck getting over 1000 on an RTI ramp with a set of custom 45" front leafs, and a set of stock '89 rear leafs and a simple shackleflip. I've posted the pics dozens of times, they should be easy to find.

If you have the option to go with a link suspension with either coils or coilvers, I wouldn't even waste time with leaves anymore.

 

[72k5mike]

Alright, thanks Greg. Thats pretty much what I wanted to hear. Btw, what was the rate of your custom leaves?

 

[Greg72]

About 240Lbs/in...

45" long (+1" over stock) with the axle position located 1" forward as well.