Jump to content

Power steering gear box


Coach23
 Share

Recommended Posts

Well the gearing is close to the same, as is the torsion bar size. The only upgrade you can get by going to a newer style box is you can get it in a 2.5 turn lock to lock fast ratio. If you're going to replace it I would recommend going with the OEM unit. Faster steering ratio is great when driving down the road, but you'll have regrets as soon as you try to turn into a parking space.

Link to comment
Share on other sites

Well the gearing is close to the same, as is the torsion bar size. The only upgrade you can get by going to a newer style box is you can get it in a 2.5 turn lock to lock fast ratio. If you're going to replace it I would recommend going with the OEM unit. Faster steering ratio is great when driving down the road, but you'll have regrets as soon as you try to turn into a parking space.

Hi Dan,

I was under the impression by `74 the steering gears were "variable ratio" and the design intent was to reduce the number of turns progressively in situations such as tight maneuvering like parking? I have fast steering boxes in `60`s cars (although not variable ratio) and the power assist is so great there is no extra effort required by the driver.

Tom Mooney

Link to comment
Share on other sites

Regrets with a 74 Unit or my oem unit when parking ? Lol

Regrets with the 74 unit. The OEM unit was designed for the car.

Hi Dan,

I was under the impression by `74 the steering gears were "variable ratio" and the design intent was to reduce the number of turns progressively in situations such as tight maneuvering like parking? I have fast steering boxes in `60`s cars (although not variable ratio) and the power assist is so great there is no extra effort required by the driver.

Tom Mooney

The 1974 units are a strait ratio. Some of the 60's gears were variable ratio. The difference between strait and variable ratio is the teeth on the sector shaft and ball nut. The teeth will be pointed on a variable ratio gear which causes the ball nut to move faster when out near lock. This will give you a faster feel without really changing the ratio. The standard ratio will have squared teeth, and move the same speed throughout the turn.

The issue you run into going from the older style box to the newer is the old box uses a 3 1/2" housing and the new uses a 3". The 3" doesn't travel as far as the 3 1/2". This causes you to lose turning radius.

As for the fast ratio difference in feel, no matter what box you use the power steering pump will still put out around 100 - 900 psi. You won't have to muscle the steering to make it work either way. But there will be a noticeable difference when cutting the amount of turns from around 4 turns down to 2.5.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

×
×
  • Create New...