Ron Pope Motorsports                California Custom Roadsters               

Steering at Low Speeds (i.e. Parking Lots)

rbsWELDER

Active Member
I have a Corvair Steering Box in my Bucket. It is very difficult to turn the wheels at low speeds (i.e. Parking - It steers like an old Mack truck). This is the primary reason that my wife will not drive the T.

I had planned to convert over to a Half Rack, this winter, but several people have told me that the parking lot steering does not improve. However, a few people say it does improve. So?????

Then I recalled that a few Nationals ago, an NTBA mentioned that he had a design for Power steering for a T. I am trying to contact him, to see if he ever documented the plan. Unfortunately, I do not have his contact info, so I am working through a third person.

Thoughts???
 
I think Unisteer makes a power steering unit that will work. Mount it like @lincolnuT did? I would first try more caster if you have less than 8 degrees.
 
Mark, check your caster. My car was hard to steer at low speeds like yours. In the process of trying to cure a death wobble I checked my caster and found it was 9 degrees. I backed it off to 5 degrees and it felt like I had power steering! It also cured my death wobble!!
 
I agree with Lee_in_KC. General rule of thumb is less caster makes the car easier to steer at slow speed but can decrease stability at road speed. Another thing that can effect it is the kingpins through the spindle bushing and especially the thrust bearings the spindle sits on. If those were put in upside down where water could easily get in they could be pretty rusty or even frozen. Both could cause quite a bit of drag. Their is also a kit available that replaces the bushings & pins w/needle bearings & stainless machined pin. I've used them a few times and the difference is night & day and truly like adding power steering. Typically used in a heavier straight axle car.

My current car is sitting at 7° caster w/Vega cross steer & small 12" steering wheel and I can use the palm of one hand when creeping along at slow speeds. Same results w/a corvair box as well.
 
Can one of you fellows point me to a website, where it shows how to measure and adjust caster?

Thanks!
 
I use simple magnetic inclinometer's on each king pin. You can get away with one. They are inexpensive and can be found at home supply stores. Generally I use bottom bar for wheelbase and top for caster. Hopefully your spring eye's are on pivots and or your spring perch has built in caster. Otherwise you can run into spring bind. Adjustment is made using four bar or hairpin ends attached to axle.
2019-10-08 13.35.27.jpg 2019-10-08 13.35.52.jpg
 
I use one similar to the Jim has shown. Around 5 to 10 bucks depending on where you buy it.
038987110061-jpg.15211
 
I use simple magnetic inclinometer's on each king pin.
Since you never directly say what you are measuring, I assume it's caster, not king pin inclination ..... right ???
To measure KPI, you would rotate the inclinometer 90° ???
 
Since you never directly say what you are measuring, I assume it's caster, not king pin inclination ..... right ???
To measure KPI, you would rotate the inclinometer 90° ???

The discussion is about caster is it not?? KPI would indicate camber. It was just a quick picture I took heading out the door for work.
 
After staging for the Mooresville's Veteran's Day Parade, yesterday, I think that I have mislead myself and the rest of you on this problem. My "hard to turn" is at zero miles per hour (i.e. when the T is not moving!) like in the corners of a three point turn.

So Mike Wade - Will the half rack improve this?

One of the NTBA guys said that I could go to power steering by using a "144 Saginaw Steering Box" and a "Type 4 Steering Pump". However, when I search those, nothing comes up with those exact names.

Thoughts?
 
....
 
Last edited:
Mark I still think your main problem is where your steering wheel is at in the car. Yes the Rack will help the parking lot turning, but only if you change the steering column at the same time or the rack first and then the column to finish up the improvements.
I suppose that power steering will help but U think the other options are better. The power steering will have to be hyd or electric so you will have many more problems in the install and more things to wrong in the long run...JMHO...….
 
G'day RB,
LincolnT and others are correct in what they say, the first order of things is to have the steering wheel in a position that you can exert leverage on it correctly. We had this sort of problem in the early Clubman cars we built not understanding the importance of the position (mainly the height so all our early cars had the wheel too low). The other thing that comes to mind is that the MGB (similar weight to a T) historically has heavy steering at parking speeds, they have 7 deg caster which was designed in when the original plans were drawn up and cars were using cross ply tyres.. By the time the cars came off the production line Radials were in use and the 7 deg caster caused the steering to be heavy at parking speeds. There has been a mod available for some years which reduces the caster to 3 deg and it improves the steering feel quite markedly. Hope this is helpful.
Regards,
 
Yes the caster will help with the low speed steering but please only change that after you make the other changes and then only as a last resort if it is around 7 degrees now.. Most Buckets work better with 5 to 8 degrees caster when you are making turns at the corner and will help with the dreaded death wobble....
 

     Ron Pope Motorsports                Advertise with Us!     
Back
Top