Astro vans and R&P's

We have had two Astro van owners who where successful installing a R&P steering on their vans and one that wasn't.Astro's suffer badly from going threw idler arms even when using Moog problem solvers.The Ford R&P's solve that problem.

Here I am looking for comments on bump steer and archermen(sp) angles etc.:confused:

If you draw a line from the upper inner shaft pivot point, and the lower inner A frame pivot, your inner pivot of the R&P should line up. If not your going to get bumpsteer, the more off it is, the worst the bumpsteer.
When using a R&P from a different car, use one from a steer behind the spindle rack, they are stronger because a steer in front uses the pull of the tires to help power it, and a behind has to push it it's self, so their built stronger.
If you use one from a Caviler type, it has the tie rods mount to the center. That way the arc of the tie rods will have less arc at the spindle arm mount, and cause you less bumpsteer. If you use one from a MM II type rack and it's to wide or to narrow you'll get a smaller arc and it'll cause more bumpsteer.

The arckerman, Unless you change your spindles or bend the tie rod mount, it will not come into play.

(I copied this)
The ackerman is an important requirement for wheels steered around separate axes is that the inside front wheel must turn at a sharper angle than the outside wheel. This is due to the fact that the inside wheel moves through a smaller arc. The difference between the inside and outside steering angles progressively increases as the wheels are turned more sharply (higher lock angles). At the low steering angles typical of highway speeds, differential steering is relatively unimportant.


Pat

Thanks for the info.The suggested R & P is a 1994 Mustang.

Anyone else care to comment??.

While mocking things up, I use a bump steer fixture and dial indicators to set things up and minimize bumpsteer. A bit of studying and some time moving components around before finalizing the design will pay dividends in a better handling front end!

Also a good plan to study the length of the steering arm off the spindle.....too long and your turning radius gets huge!