Trying to buy only once.

[OJ1988]

Seems to me it would make moree sense to correct pinion angle with shims as apoosed to changing control arm mounting location.

But, control arm mounting location / angle plays a much more important roll than that anyway.

[SCOTI]

Originally Posted by OJ1988

Seems to me it would make moree sense to correct pinion angle with shims as apoosed to changing control arm mounting location.

But, control arm mounting location / angle plays a much more important roll than that anyway.

It's not about just changing pinion angle.... it's making changes relative to the vehicles COG.

When it get's lowered via shorter or relocated springs, it changes the geometry of the T/A orientation. By moving the front mounts, you're basically putting things back where they were before altering the height from stock. While moving the front mounting points, you can also optimize them & dial in the instant center.

[OJ1988]

Originally Posted by SCOTI

It's not about just changing pinion angle.... it's making changes relative to the vehicles COG.

When it get's lowered via shorter or relocated springs, it changes the geometry of the T/A orientation. By moving the front mounts, you're basically putting things back where they were before altering the height from stock. While moving the front mounting points, you can also optimize them & dial in the instant center.

I know, I was refering to the presious post, that seemed only concerned with correcting pinion angle.

I said it play a much greater roll than pinion angle in the post you quoted.

[OJ1988]

And like I have stated several times..

We are all talking about handling here, right? Thats what the op wants. Thats what Hoctkis kits are for, thats what LNolimit is about, thats what HTH is about.

When setting these trucks up for improved handling, everyone is lowering these trucks, at least a small amount.

Why is it then, that HTH is the only one saing to lower the control arm mounts, and the rest are saying don't touch them, or flip them, which raises the mount.

[robnolimit]

IMHO, the placement of the trailing arm pivit point has to do with Rate-of-Rise, or Anti-Squat, depending on your vocabulary. This all has to do with tire loading and unloading. If there is 100% force avail to accelerate, some is used for traction, and some is used for direction (forward motion). If the mount is high, a larger percentage is used for traction (force down on the tire) and a smaller percentage for acceleration (force pushing the truck forward) My silver F-100 has 57% nose wieght, most C-10 are around 56%, Camaro's are around 52%, and a cup car is around 50%. Yes, I'd like to see the mount as low as possible - as long as the tire sticks. Since our trucks are light in the rear, we need more force on the tire from the suspension. Yes by raising the mount, we are giving up acceleration, BUT, as soon as the wheel spins, you've givin up accelerating anyway. It's all a balancing act. pinion angle is set when you weld the pads on, or with shims.

[OJ1988]

Makes since
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[Robznob11]

yes that does and maybe that is why I got this info from him. other than our trucks everything he does is for cars that did not come with a trailing arm suspension so maybe they shoot for an arm that runs nearly parallel to the ground for what ever reason. now also im thinking he may have told me It would be better for me to fix my pinion angle with the arm because I have moved my engine and tranny packag back about 2.5" enough to have to compleatly rework the fire wall and also the f body headers clear the ds lower controll arm by a good inch. this changes my % ratio front to back as opposed to a stock truck also with the body drop I have a lower center of gravity. I know that block or shims under any rear are not good for many reasons and the thicker they are the worse it is. I know that the arm location is not the correct way to fix pinion because the other geomotry is more important but maybe It was feasable for me because of my other mods. any how like I said Im going to do a real world test when I get it on the street and If It does not act right then I will play with the location. but I see no need to do the work If It hooks the way it is. I still hate the thought of running shims though because 4* puts me even Id have to go thicker to get a true 2* down like recommended and because of the custom engine set up and location I have played with the tranny angle and thats the best I can get because of floor, exhaust, oilpan, and drive shaft loop clearance. because my engine is back so far it puts the front of my driveshaft alot closer to the loop and I don't really want to hack up a 200 piece not to mention the extra work and floor clearance required. But something all should know even though there is fact behind most of the suspension talk on the board what works for one won't work for all because all trucks are different acourding to what we add to them and the only way to get a optimum set up is to 4 corner scale the truck and then set it up. I think it is great to kick around ideas though because thats how someone finds the next best trick.