Rack and Pinion question

[AustinBelair]

I'm about to order the Unisteer setup and the guy at Unisteer pointed out 2 things.

1. Since we're running an LS motor, the line pressure needs to be dampened. He said the rack is a low-flow and the LS power steering pump is high flow. Has anyone ran a regulator in the high pressure line to reduce the line pressure?

2. Since were are doing a 3/4 drop (2" Spindles and 1" springs) he said that anything over 2" drop would create a lot of bumpsteer. Is there a cure for that?

Anyone have input on those two items?

[Goats86]

The drop spindles will not change the arm location. Only the 1 inch drop springs.

[robnolimit]

Pressure reducers/regulators are avail from many sources, Speedway, KRC, Kugal, ... and have been used for years by hot rodders pairing GM pumps with Mustang II racks to reduce the twitchy feelings from the higher pressure pumps.

The bump steer concept is interesting. Goats86 is partially correct, or completely correct, depending on the set up. Drop spindles, if manufactured correctly, drop spindles should not have any change to the vehicles bumpsteer curve. Also, if the suspension is designed well, a drop spring should have no real effect on the bump curve. - BUT, the suspension WILL be operating at a different spot in the curve. Here's test. Put a 100 lb girl in the drivers seat of a Camry. The suspension doesn't drop much. It drives fine with no noticeable bumpsteer. Now, add three 200 lb guys. The car not sits 2" lower (just as it would with 2" shorted springs and only the driver) Do you think she feels the added bumpsteer from the car being lowered?

*** ALL cars and trucks have some bump-steer. It can be plotted on a graph as it relates to suspension travel, and in a 3D graph if you add steering angle. Most well designed suspensions would show less than .030 bump per inch of travel. Bump can also be a tuning tool to add 'Toe-Out' in a corner to help reduce understeer. I know you have all heard "...Ours has NO bump-steer..." well, that's B.S. The only way to have '0' bump is to lock the suspension and have '0' travel. Sad to say it, but the '0' bump stuff is a lie. Keep that in mind.

[AustinBelair]

Rob,

I was about to order the Unisteer but called your shop today and spoke to a nice lady. Does your rack come with the shaft to mount to an Ididit column? That was one of the more attractive things about the US setup.

Also, yours is based off of a 2000 Silverado. Those didn't come with LS motors (I didn't think) so will your rack handle the PSI of an LS pump?

[andrewmp6]

In 99 when they changed the body style the truck got ls motors in them.

[robnolimit]

Originally Posted by AustinBelair

Rob,

I was about to order the Unisteer but called your shop today and spoke to a nice lady. Does your rack come with the shaft to mount to an Ididit column? That was one of the more attractive things about the US setup.

Also, yours is based off of a 2000 Silverado. Those didn't come with LS motors (I didn't think) so will your rack handle the PSI of an LS pump?

Our kit includes the lower U-joint, the lower shaft, the center U-joint, and the support bearing. From that point, you will need 8" to 12" of 3/4"DD shaft, and an upper U-joint to fit the column. We don't include this because many people are changing columns, and that means different shaft length and different U-joints. We do have these items available. If you are changing columns, I suggest the IDIDIT 'short' version C10 column, we haelped design these with rack & pinion steering in mind. As far as the pump, these racks have no problem with hi-pressure and type-II pumps. You can even use the OE hoses from a 2000-2008 1500 2wd.