Steering: Avanti turning radius

[Springstreet]

My Avanti now has a turning radius of about 48 feet! (Stock is 37.9') It has new wide tires, quick steering arms, a 37" wide sway bar ( at the bracket bends) and a Steeroids Rack and Pinion unit. My mechanic says the problem is my purchase of quick steering arms. I say it is the lack of travel (5.7 inches) of the rack he chose. We both say one tire rubs on the sway bar. I say put in a new stop for the rack (6.1" of travel) and find a narrower sway bar. He says we have full lock to lock at the spindle stops. Who is right?

[Hawklover]

I had to remove the quick arms from my Avanti!!........impossible to park and almost impossible to turn the wheels:-(
Put back the arms from 1964 and bliss:-)

[Buzzard]

Hi Hawklover,
Did your car have power steering? I'm asking because I was going to use the quick arms on my PS equipped 1983 Avanti.
Bill

[Hawklover]

Yes it did, and has 205X75X15 tires on it. If your car is stopped and the wheels have to be turned.......FARGETABOUTIT!

Hi Hawklover,
Did your car have power steering? I'm asking because I was going to use the quick arms on my PS equipped 1983 Avanti.
Bill

[PackardV8]

My Avanti now has a turning radius of about 48 feet! (Stock is 37.9') . . . He says we have full lock to lock at the spindle stops. Who is right?

The fact and the statement are incompatible. Have you personally, visually verified that it hits the stops on both sides? Most R&P don't have sufficient travel to get there without the quick steering arms.

jack vines

[studegary]

Most of what you have done has no effect on turning radius.

Without checking it myself, I would say the rack does not give enough travel.
IF it goes to the spindle stops, you would have the same turning radius as originally. I think that you are probbly only going to the rack stops. This is your limiting factor.
I would like for your "mechanic" to explain to me how the quick steering arm changed the turning circle (it just gets to the steering limits with less turns of the steering wheel).

If I am incorrect or missing something, others here can correct me.

[studegary]

I do not know what year your Avanti is.
The quick steering arm came about to solve the problem created by the different gearing of the "fork lift" steering box that was used on some non-Studebaker Avantis.
I do not recommend using the quick steering arm on Studebakers with the original steering box.

[Springstreet]

[PackardV8]

Without checking it myself, I would say the rack does not give enough travel.

X2. Is this an end pivot or center takeoff rack? I've never found an end-steer rack with enough travel to get to the Stude stops.

Does anybody think I'll get close to the stock 37.9 foot steering radius if I can hit the spindle stops?

Why would it not?

jack vines

[karterfred88]

Springstreet, with the tie rod ends disconnected, take one of your wheel/tires and turn full left or right to the lock-stop. Put a ruler, centered with the tie rod end hole of the steering arm. Have a friend turn the wheel/tire all the way the opposite way till it stops, while you hold the ruler and find the new spot the hole is at. That is the distance you need to have for a full tight turning radius. I don't have short arms, but my guess is that you need something like 6.5 to 7 inches to get full lock to lock. That is one of the reasons trying to adapt a rack and pinion into an Avanti is so hard, even with a "center steer" rack and short steering arms you will come up a little short of maximum. If you hit the stops both ways you will be close to original turning radius, but you will be scrubbing either the inside or outside tire, as the steering arms and spindles have NO Ackerman built in, the original steering system, using the center bell crank pivot, produced the Ackerman effect by the different distance the inner and outer tie rods travel, due to the circular motion of the mount points of the inner tie rod ends.

[Springstreet]

[karterfred88]

If you can get "close enough" with the "travel rack" set up. You can get back the Ackerman, by bending both trailing arm short steering arms about 15-20 degrees inward. For perfect, you will have to run a tram gage from the lower center of the king pin swivel to the center of the rear axle (actual center not the pumpkin) and with the wheels perfectly straight ahead bend the arm till the bolt hole for the tie rod is exactly in that line. Repeat for other side--takes nerve and a lot of heat, trail and error. The Studebaker arms are almost perfectly at a 90 degree angle from the spindle, lowered on the ends to get an equal or approximately equal height to the lower control arm so the tie rod follows the control arm to minimize bump steer. All the Ackerman effect is by geometry of the bell crank and tie rod ends--think go-kart front end, looking straight down at the bell crank center pivot, and watching the arc of the inner ends, causing one to travel further than the other, creating the effect. It's not perfect, and neither are modern cars. But, there are other components in the newer suspension that "take up" some of the difference, some is built in at the spindle, some in control arm movement. Stude front ends are very basic, not much other motion to offset the lack of Ackerman, and it will have some effect on turn in and center corner feel, as well as tire wear which makes them look like they are not toed in or out properly. Good luck!

[Springstreet]