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**robnolimit** · 01-13-2011, 01:39 PM

Our focus on the steering link has to do with the shortcomings of the stock geometry. So far, our measuring and testing has shown this to be a problem. With stock parts we see that the trucks have about 3 degrees of bumpsteer (toe out) in 3" of compression, and 4 degrees of of bump out in 3" of droop. (both starting at ride hieght) Next, the stock Caster angle is set to be in 1* to 2* range. This is great if you have a set of Tiger Paw 78 series tires. But, it's the new millenium, and low-pro radials want more caster to keep them planted. If you tip the spindle back to gain caster, the steering arm lifts, and the outer Tie Rod End pivit point raises, and the steering geometry gets even worse. If you combine that with some drop springs, bags, or a drop crossmember, the angle of the TRE will start to max out. - this thought will lead you back to the center link as a solution to many problems of handling performance.

"Pancaking" the crossmember, (sectioning off some of the bottom), Raising the crossmember, or using a dropped crossmember, such as PB Dropmember, all have one thing in common, and that is to gain ground clearance for the "Extreme-low" crowd. If you look at a stock chassis, 63-87, the bottom of the front crossmember is about 1 3/4" below the bottom of the main frame rails. this tends to be the first thing to wipe off highway reflectors as you get the truck closer to mother earth. All three mods are trying to gain clearance. Pancaking off the bottom doesn't change anything else. Raising the stock crossmember will drop the truck by the amount raised, but cam create some steering and motor mount issues. Aftermarket dropped crossmebers will get you the drop, the clearance, and help solve some of those issues, but at a price. Many ways to skin a cat.

On swaybar links, I guess yor looking at the rear bars. Getting the rab to travel int he same arc as the suspesion is a plus, so that means tring to get the swaybar arms sort of parallel with the trailing arms. Just a note here, a longer 'link' connecting the swaybar to the axle is a plus. Also, try to keep the angles of the bar-link, and link-axle (or arm) to be 90* at ride hieght, this will help ease the angle through the travel. If you need some really cool swaybar link connectors, look at the RideTech swivel-links.

For those interested in the process to raise the stock crossmember, that may be comming up on our project C-10, the JT.

01-13-2011, 01:39 PM	#321
robnolimit Senior Member Join Date: Jul 2010 Location: Dandridge, Tn. USA Posts: 2,226	Re: Make it handle Our focus on the steering link has to do with the shortcomings of the stock geometry. So far, our measuring and testing has shown this to be a problem. With stock parts we see that the trucks have about 3 degrees of bumpsteer (toe out) in 3" of compression, and 4 degrees of of bump out in 3" of droop. (both starting at ride hieght) Next, the stock Caster angle is set to be in 1* to 2* range. This is great if you have a set of Tiger Paw 78 series tires. But, it's the new millenium, and low-pro radials want more caster to keep them planted. If you tip the spindle back to gain caster, the steering arm lifts, and the outer Tie Rod End pivit point raises, and the steering geometry gets even worse. If you combine that with some drop springs, bags, or a drop crossmember, the angle of the TRE will start to max out. - this thought will lead you back to the center link as a solution to many problems of handling performance. "Pancaking" the crossmember, (sectioning off some of the bottom), Raising the crossmember, or using a dropped crossmember, such as PB Dropmember, all have one thing in common, and that is to gain ground clearance for the "Extreme-low" crowd. If you look at a stock chassis, 63-87, the bottom of the front crossmember is about 1 3/4" below the bottom of the main frame rails. this tends to be the first thing to wipe off highway reflectors as you get the truck closer to mother earth. All three mods are trying to gain clearance. Pancaking off the bottom doesn't change anything else. Raising the stock crossmember will drop the truck by the amount raised, but cam create some steering and motor mount issues. Aftermarket dropped crossmebers will get you the drop, the clearance, and help solve some of those issues, but at a price. Many ways to skin a cat. On swaybar links, I guess yor looking at the rear bars. Getting the rab to travel int he same arc as the suspesion is a plus, so that means tring to get the swaybar arms sort of parallel with the trailing arms. Just a note here, a longer 'link' connecting the swaybar to the axle is a plus. Also, try to keep the angles of the bar-link, and link-axle (or arm) to be 90* at ride hieght, this will help ease the angle through the travel. If you need some really cool swaybar link connectors, look at the RideTech swivel-links. For those interested in the process to raise the stock crossmember, that may be comming up on our project C-10, the JT.