First of all, Hebert...if you have a sbc engine, your stock front springs are going to be too firm. Somebody else already mentioned this. You have springs designed to carry an engine weighing somewhere around 650 pounds but your sbc engine weighs somewhere around 500 or a bit less if you have aluminum manifold and heads, so you need slightly weaker springs or a 150 pound friend you can tie to the front of your truck. You need help from somebody who knows what they're doing, too. A person before you made changes to the fundamental design of the truck without considering the downstream effect. This isn't to say the original 6 and the original springs rode like a dream but their springs were matched to the weight. I don't know where you are in Texas, but you might see about consulting with a spring shop. I've seen people remove leaves from these springs to make them ride softer, but most of those people have no idea what they're doing and honestly anything that might in any way cause risk of a broken main leaf is something you never want to do. In your case I would look for some educated help. Jerry might be a good place to start. He has a great knowledge of this stuff and can help you dodge the pitfalls.
Ndkid, from what you've written your truck has been lowered in the front and the back and it sounds like the back might sit slightly higher than the front. I'm sorry but with I can't answer with any clarity. Your axle has been modified and I don't know what was done, by whom, if they built a fixed caster angle into it (which I never would have done), what camber angle they built into it, what kingpin inclination degree they used...anything. Sorry but I feel like a doctor when a patient calls up and says "doc, I feel bad. What do I have?" I'd say if yours drives right and doesn't wander or scrub the tire treads off too fast, leave it and enjoy it.
Let me try to show an example of the caster angle:
http://i1154.photobucket.com/albums/p535/JonGoodman/Caster%20at%200.jpg The floor is pretty well level. If I could get in there to take a better picture, you could see the needle is just a hair from zero
http://i1154.photobucket.com/albums/p535/JonGoodman/Caster%20at%203%20degrees.jpg And with this little gizmo held right up against the kingpin/steering knuckle you can see it is 3 degrees positive. I don't hold it up against the axle. That doesn't tell me squat because I don't know what it bears to the kingpin line. Three degrees is what I want for my starting point. I know at this spot it will run straight and if it steers a little hard, I can go lower.
And I can tell you what the factory wanted your truck to have when they built it:
Caster angle---1.75 degrees positive plus or minus .5 degrees
Camber angle---1 degree plus or minus .5 degrees
Kingpin Inclination---7°10' plus or minus 1°
Toe-out on turns---outside wheel 20 degrees, inside wheel 23 plus or minus 2 degrees.
Them's the numbers. If your springs are good and your tires are the same height, your wheel bearings and kingpins are good, your tie rod ends and connectors are good (not egg shaped or loose), your drag link is right and steering box adjusted correctly and you have the front end set up with these specs, it will drive pretty much like a new one. And that isn't a bad thing. You can make the front wheels track better by adding a degree to the caster (total of 3 degrees or less), but it will not steer as easily. Study the way the angles work, see why caster works in the first place and you'll see why larger caster angles increase steering effort. Bikes and some motorcycles have (by comparison) extreme caster angles but they have very little weight to speak of over the front tire.
Jon
